Help:CS1 errors

Template:Pp-semi-indef Template:Wikipedia how to Template:Skip to top and bottom This page describes the error messages reported by the Citation Style 1 and Template:Cs2 citations, what they mean, and how editors might resolve the errors. Category:CS1 errors is the general errors category and Category:CS1 maintenance is the general maintenance category.

Errors issued by Wikipedia's <ref> system, in which citation templates are typically embedded, can be found at Help:Cite errors.

Controlling error message display

Preview messages

When editors preview an article, MediaWiki displays a preview message box under the Preview header. When Citation Style 1 and Template:Cs2 templates have error or maintenance messages, Module:Citation/CS1 summarizes those messages in the preview message box. Such a message box might look something like this:

Remember that this is only a preview. Your changes have not yet been published! → Go to editing area

Script warning: Template:Color; messages may be hidden (help).

Script warning: Template:Color; messages may be hidden (help).

The summary messages have three components:

1. 'Script warning:' – this prefix is provided by MediaWiki;
2. a colored (Template:Color or Template:Color) message that identifies the type of template that has a message with a link to that template's documentation; wrapper templates with messages will show the name of the wrapped template, and;
3. 'messages may be hidden' – the message suffix with a help link to this page.

Preview messages in the preview message box cannot be hidden. The preview message suffix 'messages may be hidden' means that the template's message(s) may not be visible. To learn how to show or hide template messages, see the next section (

1. REDIRECT Template:Section link

).

Error and maintenance messages

<section begin="show_error_messages_help_text" /><section begin="show_all_messages_help_text" />By default, Citation Style 1 and Template:Cs2 error messages are visible to all readers and maintenance messages are hidden from all readers.

To display maintenance messages in the rendered article, include the following text in your common CSS page (common.css) or your specific skin's CSS page and (skin.css).

(Note to new editors: those CSS pages are specific to you, and control your view of pages, by adding to your user account's CSS code. If you have not yet created such a page, then clicking one of the .css links above will yield a page that starts "Wikipedia does not have a user page with this exact name." Click the "Start the User:username/filename page" link, paste the text below, save the page, follow the instructions at the bottom of the new page on bypassing your browser's cache, and finally, in order to see the previously hidden maintenance messages, refresh the page you were editing earlier.)

<syntaxhighlight lang="css">:root .mw-parser-output .cs1-maint {display: inline;} /* display Citation Style 1 maintenance messages */</syntaxhighlight>

To display hidden-by-default error messages:

<syntaxhighlight lang="css">:root .mw-parser-output .cs1-hidden-error {display: inline;} /* display hidden Citation Style 1 error messages */</syntaxhighlight>

Even with this CSS installed, older pages in Wikipedia's cache may not have been updated to show these error messages even though the page is listed in one of the tracking categories. A null edit will resolve that issue.

After (error and/maintenance) messages are displayed, it might still not be easy to find them in a large article with a lot of citations. Messages can then be found by searching (with Ctrl-F) for "(help)" or "cs1".

To hide normally-displayed error messages: <syntaxhighlight lang="css">:root .mw-parser-output .cs1-visible-error {display: none;} /* hide Citation Style 1 error messages */</syntaxhighlight>

You can personalize the display of these messages (such as changing the color), but you will need to ask someone who knows CSS or at the technical village pump if you do not understand how.

Nota bene: these CSS rules are not obeyed by Navigation popups. They also do not hide script warning messages in the Preview box that begin with "This is only a preview; your changes have not yet been saved".<section end="show_all_messages_help_text" /><section end="show_error_messages_help_text" />

Properties category highlighting

<section begin="prop_cat_highlight_help_text" /> Module:Citation/CS1 adds properties categories to some CS1|2 citations. Unlike errors or maintenance needs, there is no message when a properties category is added. Properties categories may be temporary or may be perpetual. Editors can use CSS to add special styling to CS1|2 template renderings that will highlight a citation that added a properties category. For example, this template uses a long volume name:

{{cite book |title=Title |date=May–Jun 2021 |volume = 1: Long volume}}

Template:Cite book

If you add this to your CSS that citation will render with a Template:Background background:

<syntaxhighlight lang="css">.cs1-prop-long-vol {background: #FFC;}</syntaxhighlight>

Add one or more of these (with appropriate styling) to your CSS to highlight template renderings when those templates add the associated properties category:

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-foreign-lang-source {}</syntaxhighlight> – subcategories of

1. REDIRECT Template:Category link

• From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-foreign-lang-source-2 {}</syntaxhighlight> –

1. REDIRECT Template:Category link

• From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-interwiki-linked-name {}</syntaxhighlight> – author, contributor, editor, interviewer, translator name(s) linked to another language Wikipedia

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-interproj-linked-name {}</syntaxhighlight> – author, contributor, editor, interviewer, translator name(s) linked to another MediaWiki project

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-location-test {}</syntaxhighlight> –

1. REDIRECT Template:Category link

• From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-long-vol {}</syntaxhighlight> –

1. REDIRECT Template:Category link

• From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-script {}</syntaxhighlight> – subcategories of

1. REDIRECT Template:Category link

• From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-tracked-param {}</syntaxhighlight> – subcategories of

1. REDIRECT Template:Category link

• From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-unfit {}</syntaxhighlight> —

1. REDIRECT Template:Category link

• From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.

<syntaxhighlight lang="css" class="" style="" inline="1">.cs1-prop-year-range-abbreviated {}</syntaxhighlight> –

1. REDIRECT Template:Category link

• From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.

<section end="prop_cat_highlight_help_text" />

Most common errors

• #ISBN / Date incompatibility, ~41k pages
• #Cite <template> requires |<param>=, ~34k pages
• #Cite uses generic name, ~28k pages
• #<periodical>= ignored, ~21k pages
• #Citation without a title of any form, ~19k pages
• #Bare URL without a title, ~12k pages

|access-date= requires |url=

<section begin="accessdate_missing_url_help_text" />Template:Help desk

The Template:Para is the date that the online resource addressed by Template:Para was added to the article. If Template:Para has been included in the citation without Template:Para then this message appears. If the citation does not use a web link, then Template:Para is redundant and should be removed.

When the online resource has a publication or other fixed date associated with it, Template:Para is of limited value though may be useful in identifying an appropriate archived version of the resource. Without Template:Para, Template:Para is not considered useful.

To resolve this error, provide a value for Template:Para or remove Template:Para. Editors should try to determine why the citation has Template:Para without Template:Para. For example, the citation may never have had a Template:Para, or Template:Para may have been removed because it links to a site that violates the creator's copyright (see WP:COPYLINK), or because Template:Para was deemed to be dead. If the citation never had Template:Para or it was removed for copyright violations, remove Template:Para. When a dead Template:Para has been removed, restore the Template:Para and if possible repair it (see WP:LINKROT).

Pages with this error are automatically placed in .<section end="accessdate_missing_url_help_text" />

|archive-date= / |archive-url= timestamp mismatch

<section begin="archive_date_url_ts_mismatch_help_text" />Template:Help desk

Archive.org and Archive.today URLs have a 14-digit snapshot timestamp. This error message is displayed when the archive snapshot date is not the same as the date stated in Template:Para.

To resolve this error, make sure that Template:Para and Template:Para refer to the same snapshot. This could mean that values assigned to either or both parameters need to be updated. To get the correct Template:Para value, view the archived page's source, looking for a line near the bottom that starts with "FILE ARCHIVED ON". The archive date should appear on that line.

Pages with this error are automatically placed in .<section end="archive_date_url_ts_mismatch_help_text" />

Pages with this error in the tracking category can be fixed by the bot WP:WAYBACKMEDIC. Requests to run the bot can be made at WP:URLREQ.

|archive-date= requires |archive-url=

<section begin="archive_date_missing_url_help_text" />Template:Help desk

Template:Para, identifies the date that the web resource was archived. Without a matching Template:Para parameter, Template:Para is meaningless.

To resolve this error, provide a value for Template:Para or remove Template:Para

Pages with this error are automatically placed in .<section end="archive_date_missing_url_help_text" />

|archive-url= is malformed

<section begin="archive_url_help_text" />Template:Help desk

Archive.org allows a variety of URLs to access snapshots of an archived page. Some of these are:

https://web.archive.org/web/YYYYMMDDhhmmss/http://www.example.com – a single snapshot; this is the preferred form for use with Template:Para

https://web.archive.org/web/*/http://www.example.com – a wildcard search results page; useful for locating an appropriate snapshot but not appropriate in a citation

https://web.archive.org/web/201603/http://www.example.com – incomplete timestamp; archive.org returns the most recent snapshot

https://web.archive.org/save/http://www.example.com – saves a new snapshot of the current target; do not use this form

There are two forms of the basic URL:

https://web.archive.org/<timestamp>/... – the old form

https://web.archive.org/web/<timestamp><flags>/... – the new form

The error message identifies the reason for the message. The reasons are:

Template:Error-small – the archive.org URL is the save command

Template:Error-small – web/ was expected but something else was found

Template:Error-small – the timestamp portion of the URL path is not 14 digits

Template:Error-small – the flag portion of the URL path (if present; new form URLs only) is not 2 lowercase letters followed by an underscore: 'id_'

Template:Error-small – liveweb.archive.org is a deprecated form of the domain name

When the archive.org URL has any of these errors, Module:Citation/CS1 does not link to archive.org in normal article view and emits an appropriate error message.

However, in article preview mode, the module creates a modified link to archive.org that uses a partial timestamp with * wildcard suffix. This new URL links to an archive.org calendar view so that editors may more easily select a suitable archived snapshot from those available at archive.org to fix the malformed Template:Para link. (If no snapshots have been archived at archive.org, and the cited page is still live, this link also allows editors to save the first snapshot of the page at archive.org.)

To resolve this error, choose the URL of an appropriate snapshot from those held at archive.org. Search for the target URL at archive.org.

Pages with this error are automatically placed in .<section end="archive_url_help_text" />

|archive-url= requires |archive-date=

<section begin="archive_missing_date_help_text" />Template:Help desk

Template:Para, identifies the date that the web resource was archived.

To resolve this error, provide a value for Template:Para (see acceptable date formats in MOS:DATEFORMAT). For web resources archived at archive.org, the archival date can be found in the Template:Para; for resources archived at webcitation.org, the cache date is included in the archive header.

Pages with this error are automatically placed in .<section end="archive_missing_date_help_text" />

|archive-url= requires |url=

<section begin="archive_missing_url_help_text" />Template:Help desk

A properly formatted citation that includes Template:Para and Template:Para requires Template:Para. When the citation includes Template:Para, the ordering of elements in the rendered citation is changed to put the original URL first.

To resolve this error, provide a value for Template:Para. For web resources archived at archive.org, the original URL can be found in the Template:Para value; for resources archived at webcitation.org, the original URL is included in the archive header.

Pages with this error are automatically placed in .<section end="archive_missing_url_help_text" />

|arxiv= required

<section begin="arxiv_missing_help_text" />Template:Help desk

Template:Tlx requires one, but not both, of the identifier parameters Template:Para or Template:Para to specify an arXiv identifier.

To resolve this error, ensure that the template has Template:Para or Template:Para with a properly constructed value.

Pages with this error are automatically placed in .<section end="arxiv_missing_help_text" />

|asin-tld= requires |asin=

<section begin="asintld_missing_asin_help_text" />Template:Help desk

When Template:Para is used in a CS1|2 template, Template:Para (with value) must also be present.

To resolve this error, either add the missing ASIN or remove the 'broken' parameter.

Pages with this error are automatically placed in .<section end="asintld_missing_asin_help_text" />

|biorxiv= required

<section begin="biorxiv_missing_help_text" />Template:Help desk

Template:Tlx requires the identifier parameter Template:Para.

To resolve this error, ensure that the template has Template:Para with a properly constructed value.

Pages with this error are automatically placed in .<section end="biorxiv_missing_help_text" />

|chapter= ignored

<section begin="chapter_ignored_help_text" />Template:Help desk

Citation Style 1 templates Template:Tlx, Template:Tlx, Template:Tlx, Template:Tlx, Template:Tlx, Template:Tlx, Template:Tlx, as well as template Template:Tlx when it uses Template:Para or any of its aliases, do not support Template:Para and its components Template:Para, Template:Para, Template:Para, and Template:Para. The alias parameters Template:Para, Template:Para, Template:Para, Template:Para, and their components, are similarly not supported.

To resolve this error:

• use a more appropriate citation template, or
• place the content of the Template:Para parameter in Template:Para, or
• for Template:Tl, Template:Para can be used to give the name of the newspaper's section, such as "Obituaries", or
• for Template:Tl, remove Template:Para or its aliases such as Template:Para and place their content in Template:Para if appropriate
• move the content of the Template:Para parameter out of the template, before the closing </ref>

Pages with this error are automatically placed in .<section end="chapter_ignored_help_text" />

<char> character in |<param>= at position n

<section begin="invisible_char_help_text" />Template:Help desk

This error is reported for citations with parameter values that contain invisible or non-printable characters known as control characters; the error includes the position at which the character can be found. Module:Citation/CS1 detects parameter values that contain any of these characters:

• non-breaking space, U+00A0
• soft hyphen, U+00AD
• replacement character, U+FFFD
• hair space, U+200A
• zero-width space, U+200B
• zero-width joiner, U+200D (note that these are permitted as part of emoji modifiers; see note below)
• horizontal tab, U+0009 (HT)
• line feed, U+0010 (LF)
• carriage return, U+0013 (CR)
• delete character, U+007F (DEL)
• C0 control, U+0000–U+001F (NULL–US)
• C1 control, U+0080–U+009F (XXX–APC)

To resolve invisible-character errors, remove or replace the identified character. Most intentional white-space characters should be replaced with a normal space character (i.e. press your keyboard's space bar). See MOS:NBSP for guidance on insertion of intentional non-breaking spaces.

Because these characters are mostly invisible, the error message identifies the character's position in the parameter value counted from the left. Space characters between the assignment operator (the '=' sign) and the parameter value are not counted. If you move through the citation with the arrow keys then the cursor may stand still once at an invisible character, which can be removed with Template:Keypress or Template:Keypress. If you copy-paste a string to the "Characters" field at https://r12a.github.io/app-conversion/ and click "View in UniView" then the position and name of all characters is shown.

Zero-width joiner characters (U+200D) are used as a valid part of emoji modification (for example, adding a skull emoji to a flag emoji to create a pirate flag emoji). When new modifiers are added to the emoji character set, which happens one or two times per year, those modifiers need to be added to the Citation Style 1 "Configuration" module. Editors can request this addition at Help talk:Citation Style 1.

Strip markers are special sequences of characters that MediaWiki inserts as a place-holder for certain XML-like tags. These tags include Template:Tag, Template:Tag, Template:Tag, Template:Tag, and Template:Tag. The strip markers are replaced with content before the final page rendering. The module ignores math and nowiki strip markers.

To resolve strip marker errors, remove or replace the identified tag. The error message identifies the strip marker's position in the parameter value counted from the left. Space characters between the assignment operator (the '=' sign) and the parameter value are not counted when calculating the position.

Strip marker errors can also be caused by unsupported additional text or templates in parameter valuesTemplate:Mdashfor example, Template:Tl in Template:Para. Resolve the problem by moving the extraneous text outside the citation template, or by removing the extraneous text or template markup, as appropriate.

Pages with this error are automatically placed in .<section end="invisible_char_help_text" />

Check |arxiv= value

<section begin="bad_arxiv_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the arXiv identifier conforms with the arXiv identifier scheme. The identifier is checked for a valid number of digits in the article id; valid year and month values; and properly-placed hyphens, slashes, and dots.

To resolve this error, ensure that the Template:Para value is correct.

Pages with this error are automatically placed in .<section end="bad_arxiv_help_text" />

Check |asin= value

<section begin="bad_asin_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the ASIN identifier contains ten upper-case alphanumeric characters without punctuation or spaces and that if the first character is numeric, that the ASIN conforms to the rules for a ten-digit ISBN.

To resolve this error, ensure that the Template:Para value is correct.

If the Template:Para value is correct and all-numeric, use Template:Para instead and delete any Template:Para parameters.

Pages with this error are automatically placed in .<section end="bad_asin_help_text" />

Check |asin-tld= value

<section begin="bad_asin-tld_help_text" />Template:Help desk

Citation Style 1 and Template:Cs2 templates contain a test for known Template:Para values to specify the top-level domain (TLD) of a given ASIN identifier link. The list of currently supported values is:

<section begin="asin-tld_values_list" />ae, au, br, ca, cn, de, es, fr, in, it, jp, mx, nl, pl, sa, se, sg, tr, uk<section end="asin-tld_values_list" />

It is not necessary to provide Template:Para to specify the default (United States). If you want to specify this condition explicitly, a pseudo-value of us can be given to denote this.

All these values are automatically resolved to the correct TLD following one of the schemes nn, com.nn, co.nn, z.nn, and com.

If an unsupported value is encountered, the template will issue this error message.

To resolve this error, ensure that the Template:Para value is correct.

If the value is correct, please report this at Help talk:Citation Style 1, so that it can be added to the list of supported values.

Pages with this error are automatically placed in .<section end="bad_asin-tld_help_text" />

Check |bibcode= <message>

<section begin="bad_bibcode_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the bibcode identifier has the proper format. Bibcodes are expected to match these requirements:

length must be 19 characters (<message> = '')

characters in position(s): (except as specified otherwise, violations produce '' in the <message> portion of the error message):

1–4 must be digits and must represent a year in the range of 1000 – next year (<message> = '')

5 must be a letter

6–8 must be a letter, ampersand, or dot (ampersand cannot directly precede a dot; &. (<message> = ''))

9 must be a letter or dot

10–18 must be a letter, digit, or dot

19 must be a letter or dot

To resolve this error, ensure that the Template:Para value is correct.

Pages with this error are automatically placed in .<section end="bad_bibcode_help_text" />

Check |biorxiv= value

<section begin="bad_biorxiv_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the bioRxiv identifier has the proper form. There are two valid forms, each beginning with bioRxiv's doi directory indicator and registrant code (10.1101) and followed by:

six numeric characters without punctuation or spaces:

Template:Para

###### – 6-digit bioRxiv identifier

ymd format date prefix followed by six numeric characters without punctuation or spaces followed by optional version:

Template:Para where:

yyyy.mm.dd. – represents a date no earlier than 11 December 2019 (2019.12.11.) and no later than tomorrow's date; date must be a valid date

###### – 6-digit bioRxiv identifier

v# – optional version indicator

A common error is to include the bioRxiv URL (Template:Red10.1101/######}}).

To resolve this error, ensure that the Template:Para value is correct.

Pages with this error are automatically placed in .<section end="bad_biorxiv_help_text" />

Check |citeseerx= value

<section begin="bad_citeseerx_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the CiteSeerX identifier has the proper format. The expected identifier is the value assigned to the ?doi= query key in the URL of a CiteSeerX document. (This query key should not be confused with a Digital Object Identifier: it should not be input as Template:Para.)

For instance, if you want to link to http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.220.7880, use Template:Para.

Pages with this error are automatically placed in .<section end="bad_citeseerx_help_text" />

Check date values in: |<param1>=, |<param2>=, ...

<section begin="bad_date_help_text" />Template:Help desk Template:Plainlist

When Citation Style 1 and Template:Cs2 templates contain date-holding parameters, an automated test is done to see if the dates are real dates that comply with a subset of the date rules in Wikipedia's Manual of Style, specifically checking for violations of MOS:DATEFORMAT.

To resolve this error, ensure that the date is an actual date and that the date format follows the Wikipedia Manual of Style's guidance on dates in the named parameter. See examples of unacceptable dates and how to fix them, below. Or, some conceptual issues to look for:

• impossible dates, such as 29 February 2011 (2011 was not a leap year)
• Template:Para must specify a day, not just a month or year
• Template:Para must specify a whole date
• misplaced, incorrect, or extraneous punctuation
• misplaced, incorrect, or extraneous spacing
• extraneous text
• hyphens or slashes instead of en dashes in date ranges (en dashes are required)
• misspelling or improper capitalization (see MOS:ALLCAPS for more detail that is not in Wikipedia Manual of Style's guidance on dates)
• other unacceptable date formats listed in MOS:BADDATEFORMAT
• more than one date in a date-holding parameter
• days of the week (such as Monday, June 6 instead of June 6)
• years before 100 AD, including BCE/BC dates. Try using parameter Template:Para instead.

See Help: Citation Style 1 for information about limitations in the CS1 citation templates' handling of date formats. The MOS section on date ranges describes how to separate dates in a date range. Do not use  , –, or Template:Tlx as these corrupt the metadata. To add an en dash, use the CharInsert edit tool or see Wikipedia:How to make dashes. You may also copy and paste this one: –. A bot is often able to correct the separator, provided the overall format is unambiguous.

Future dates in Template:Para in CS1|2 citations are limited to current year + 1; that is, for 2025, citation dates in 2026 are acceptable but citation dates in 2027 and beyond are not.

Dates prior to 1582 are treated as Julian calendar dates. Dates from 1582 onward are treated as Gregorian calendar dates. The Julian calendar was used in some places until approximately 1923. Three Julian calendar dates in the overlap period, 29 February in the years 1700, 1800, and 1900, will cause this error message because those years are not leap years in the Gregorian calendar.

The access date (in Template:Para) is checked to ensure that it contains a full date (day, month, and year) and is between 15 January 2001 (the founding date of Wikipedia) and today's date plus one day, because it represents the date that an editor viewed a web-based source to verify a statement on Wikipedia. Because editors may be in time zones that are one day ahead of the UTC date, one extra day is accepted.

Pages with this error are automatically placed in .<section end="bad_date_help_text" />

Examples of unacceptable dates and how to fix them

Issue	Unacceptable	Acceptable
Hyphen in date range (use en dash)	Template:Para	Template:Para
Slash in date range (use en dash)	Template:Para or Template:Para	Template:Para or Template:Para
Hyphen in date range (use en dash)	Template:Para	Template:Para
Missing space around en dash for range of full dates	Template:Para	Template:Para
Month capitalization	Template:Para	Template:Para
Month capitalization	Template:Para	Template:Para
Season capitalization	Template:Para	Template:Para
Future date (typo)	Template:Para	Template:Para
Access date in future (see note above)	Template:Para	Template:Para
Access date impossibly far in the past (typo)	Template:Para	Template:Para
Access date only specifies month	Template:Para	Template:Para
Ambiguous date range or year and month	Template:Para	Template:Plainlist
Bad abbreviation	Template:Para	Template:Plainlist
Nonexistent date	Template:Para
Undated	Template:Para	Template:Para
Comma in month and year	Template:Para	Template:Para
Comma in season	Template:Para	Template:Para
Missing comma in format which requires it	Template:Para	Template:Para or Template:Para or Template:Para
Non-date text	Template:Para	Template:Para Template:Green
Zero-padding	Template:Para	Template:Para
Date with slashes	Template:Para	Template:Para or Template:Para or Template:Para or Template:Para or Template:Para or Template:Para
Two-digit year	Template:Para	Template:Para
One-digit month or day	Template:Para	Template:Para
Wikified date	Template:Para	Template:Para
"mm-dd-yyyy" or "dd-mm-yyyy" date format	Template:Para	Template:Para or Template:Para or Template:Para or Template:Para or Template:Para or Template:Para
Quarters	Template:Para or Template:Para or Template:Para	Template:Para
Named dates	Template:Para or Template:Para	Template:Para
Approximate or uncertain dates	Template:Para or Template:Para	Template:Para

Check |doi= value

<section begin="bad_doi_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the prefix portion of the DOI value is correctly formatted and has what appears to be a valid registrant code. A proper DOI prefix begins with the 10. directory indicator. The remaining portion of the prefix is a string of digits and the dot character which form the registrant code. When the directory indicator is 10., the CS1|2 templates test for a valid registrant code. Valid registrant codes:

• must be composed of digits
• must be in the range:
  • 1000–9999
  • 10000–49999
• may have one or more subcodes that begin with a dot followed by digits (1000.10)
• must not be 5555 (invalid/temporary/test)

Additionally, the Template:Para value is checked to make sure that it does not contain spaces, en dashes, does not end with punctuation. Further validation of the DOI is not performed.

Do not include the https://doi.org/ scheme and domain name from a URL. A proper Template:Para value looks like Template:Para.

To resolve this error, ensure that the Template:Para value is correct.

In very rare cases, publishers have released works with a DOI deviating from the standard form. If you are certain that such a non-conforming DOI truly corresponds to the published work, then you can add accept-this-as-written markup around the identifier to suppress the error message. (Do not use this markup for DOIs, which are inactive rather than non-conforming. Instead, use Template:Para for them.)

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Check |hdl= value

<section begin="bad_hdl_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the hdl value looks like a properly defined value. The Template:Para value is checked to make sure that it does not contain spaces or en dashes and does not end with punctuation. Further validation of the hdl is not performed.

To resolve this error, ensure that the Template:Para value is correct.

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Check |isbn= value

<section begin="bad_isbn_help_text" />Template:Help desk

Citation Style 1 and Template:Cs2 templates that contain Template:Para are checked to ensure that the ISBN is the proper length (ten or thirteen digits), that the ISBN uses the correct optional separators (simple space or hyphen), and that the final check digit is correct according to the ISBN specification. Only one ISBN is allowed in this field because the whole Template:Para value is included in the citation's COinS metadata. See also Wikipedia:COinS. More than one ISBN, or characters that are not part of the ISBN, corrupt the COinS metadata and may also corrupt the link to Special:BookSources. (If relevant, they can be specified using Template:Para instead.)

The error message <type> indicator can be:

Template:Error-small – ISBN is not 10 or 13 digits

Template:Error-small – ISBN has one or more incorrect digits; look for typos and transposition

Template:Error-small – ISBN has one or more 'digits' that is not in the allowed set appropriate to ISBN length

Template:Error-small – 13-digit ISBNs must begin with '978' or '979'

Template:Error-small – 10-digit ISBNs with the mis-positioned 'X' character

Template:Error-small – 13-digit ISBN begins with '9790'; this prefix / group ID combination is reserved to ISMN

To resolve this error, ensure that the Template:Para value is correct, that only one ISBN is used, that the proper optional separators are used, and that no other text is included. Use the ISBN printed on the work rather than one retrieved from third-party sources. If both are available, use the 13-digit ISBN. When a 10-digit ISBN is used, if the check digit is a lowercase 'x', change it to an uppercase 'X'.

• Do not try to resolve the error by simply recalculating the check digit. The check digit is there to check whether the main part of the number is correct. If the ISBN is failing to validate, it is likely that there is a typo in the main part of the number. In this case, recalculating the check digit results in an apparently valid ISBN that leads to the wrong source (or to nowhere).
• If you only have a 10-digit ISBN, do use the number as-is, do not try to convert it to the 13-digit form.
• If the ISBN as printed in your source is refusing to validate, do check both the front matter and the book cover for ISBNs. It is not uncommon for the ISBN to be misprinted in the front matter but correct on the cover.
• Do preview your edit and check that the new ISBN does now link to the correct source.

In very rare cases, publishers have released books with malformed ISBNs. If you are certain that a non-conforming ISBN truly corresponds to the published work, then you can add accept-this-as-written markup around the identifier to suppress the error message. In many cases, books may have been reissued with a corrected ISBN. Use a corrected ISBN when possible.

Sometimes there are numbers assigned to Template:Para that appear to be legitimate – length is right, check digit is correct – but that aren't true ISBN numbers. This tool may be helpful.

See also Wikipedia:ISBN.

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Check |ismn= value

<section begin="bad_ismn_help_text" />Template:Help desk

Citation Style 1 and Template:Cs2 templates that contain Template:Para are checked to ensure that the ISMN is the proper length (thirteen digits), that the ISMN uses the correct optional separators (simple space or hyphen), and that the final check digit is correct according to the ISMN specification. Only one ISMN is allowed in this field because the whole Template:Para value is included in the citation's COinS metadata. See also Wikipedia:COinS. More than one ISMN, or characters that are not part of the ISMN, corrupt the COinS metadata. (If relevant, they can be specified using Template:Para instead.)

To resolve this error, ensure that the Template:Para value is correct, that only one ISMN is used, that the proper optional separators are used, and that no other text is included. Make sure that the ISMN contains exactly 13 digits.

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Check |issn= value

<section begin="bad_issn_help_text" />Template:Help desk Template:Plainlist

Citation Style 1 and Template:Cs2 templates that contain Template:Para and/or Template:Para are checked to ensure that the ISSN is the proper length (eight digits) and that the final check digit validates according to the ISSN specification. Only one each of ISSN and eISSN is allowed in this field because the whole Template:Para and Template:Para values are included in the citation's COinS metadata. See also Wikipedia:COinS. (If relevant, they can be specified using Template:Para instead.)

The ISSN and eISSN are always rendered as two four-digit numbers separated with a hyphen.

To resolve this error, ensure that the Template:Para and Template:Para values are correct, that only one value per parameter is used, and that no other text is included (allowable characters are 0–9, X, and -). If the check-digit is a lowercase 'x', change it to an uppercase 'X'. It may also be worth checking an actual hyphen (-) has been used, and not a hyphen-like character like an endash (–).

In very rare cases, publishers have released works with a malformed identifier. If you are certain that a non-conforming identifier truly corresponds to the published work, then you can add accept-this-as-written markup around the identifier to suppress the error message. In some cases, works may have been reissued with a corrected identifier. Use the corrected one when possible.

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Check |jfm= value

<section begin="bad_jfm_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the JFM identifier value looks like a properly defined value. The Template:Para identifier is checked to make sure that it has the form: nn.nnnn.nn where n is any digit 0–9. Further validation of the JFM identifier is not performed.

To resolve this error, ensure that the Template:Para value is correct.

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Check |jstor= value

<section begin="bad_jstor_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the JSTOR identifier value looks like a properly defined value. Error messages are emitted when the assigned value has some form of the string 'jstor' (case-agnostic), or has a URI scheme (http:// or https://), or has any space characters.

To resolve this error, ensure that the Template:Para value is correct.

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Check |lccn= value

<section begin="bad_lccn_help_text" />Template:Help desk

The Template:Para parameter is for the Library of Congress Control Number identifier. It is checked to ensure that the identifier is the proper length and has the correct initial digits.

LCCN is a character string 8–12 characters long. The length of the LCCN dictates the character type of the initial 1–3 characters; the rightmost eight are always digits.

LCCN format description

Length	Description
8	all characters are digits
9	first character is a lower case letter
10	first two characters are either both lower case letters or both digits
11	first character is a lower case letter, second and third characters are either both lower case letters or both digits
12	first two characters are both lower case letters

Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct and that there are no other letters, punctuation, or other characters.

When receiving this error, be on the lookout for publishers who omitted leading zeros in the LCCN following the two or four digit year. For example, an LCCN that is properly 92-035427 could be shortened in the printed work to 92-35247. When experimenting with inserting omitted zeroes, cross-check the finished number against the LCCN permalinks online.

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Check |medrxiv= value

<section begin="bad_medrxiv_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the medRxiv identifier has the proper form. The medRxiv identifier begins with medRxiv's doi directory indicator and registrant code (10.1101) and followed by:

ymd format date prefix followed by eight numeric characters without punctuation or spaces followed by optional version:

Template:Para where:

yyyy.mm.dd. – represents a date no earlier than 1 January 2020 (2020.01.01.) and no later than tomorrow's date; date must be a valid date

######## – 8-digit medRxiv identifier

v# – optional version indicator

A common error is to include the medRxiv URL (Template:Red10.1101/yyyy.mm.dd.########}}).

To resolve this error, ensure that the Template:Para value is correct.

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Check |message-id= value

<section begin="bad_message_id_help_text" />Template:Help desk

The Template:Para parameter holds the unique identifier associated with a netnews message. The value in Template:Para is checked to make sure that it contains @ between left and right identifiers. Template:Para is also checked to make sure that the first character is not < and the last character is not >. Module:Citation/CS1 adds the URI scheme news: to the value in Template:Para. If the value in Template:Para is wrapped in <...> characters, the link created fails.

Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct, that it contains @ and is not wrapped in <...> characters.

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Check |mr= value

<section begin="bad_mr_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the MR identifier value looks like a properly defined value. The Template:Para identifier is checked to make sure that it contains only digits and that it is no more than seven digits in length. Further validation of the MR identifier is not performed.

To resolve this error, ensure that the Template:Para value is correct.

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Check |oclc= value

<section begin="bad_oclc_help_text" />Template:Help desk

The Template:Para parameter is for the OCLC identifier. Only a single OCLC identifier is allowed. (If relevant, multiple OCLCs can be specified using Template:Para instead.)

The identifier must be in one of these forms:

1. prefix ocm followed by 8 digits
2. prefix ocn followed by 9 digits
3. prefix on followed by 10 (or more) digits
4. prefix (OCoLC) followed by a variable number of digits without leading zeros
5. 1 to 10 (or more) digits without prefix

Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct.

If the value is correct and larger than the currently configured limit of , please report this at Help talk:Citation Style 1, so that the limit can be updated.

A tip for fixing this error: Editors sometimes place valid ISBN, LCCN, ASIN, or other identifiers in Template:Para.

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Check |ol= value

<section begin="bad_ol_help_text" />Template:Help desk

The Template:Para parameter is for the Open Library identifier. The identifier is one or more digits followed by a last character that is either A (authors), M (books), or W (works). Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct. Do not include "OL" in the value.

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Check |osti= value

<section begin="bad_osti_help_text" />Template:Help desk

The Template:Para parameter is for the Office of Scientific and Technical Information (OSTI) identifier. OSTIs are checked to ensure that the identifier is a simple number without punctuation or spaces with a value between 1018 and . Further validation is not performed.

A common error is to include the OSTI URL (https://dx.doi.org/10.2172/Template:Red), or the OSTI DOI (10.2172/Template:Red).

To resolve this error, ensure that the Template:Para value is correct.

If the value is correct and lower than 1018 or larger than the currently configured limit of , please report this at Help talk:Citation Style 1, so that the limit can be updated.

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Check |<param>-link= value

<section begin="bad_paramlink_help_text" />Template:Help desk Template:Plainlist

These link-holding parameters and their matching title-/name-holding parameters are combined to create a working wikilink to a related article.

Parameters combined to make wikilinks

Link-holding parameter	title-/name-holding parameter(s)
Template:ParaTemplate:Dagger	Template:Para, Template:Para, Template:Para + Template:Para
Template:ParaTemplate:Dagger	Template:Para, Template:Para, Template:Para + Template:Para
Template:ParaTemplate:Dagger	Template:Para, Template:Para, Template:Para + Template:Para
Template:Para	Template:Para
Template:ParaTemplate:Dagger	Template:Para, Template:Para, Template:Para + Template:Para
Template:Para	Template:Para
Template:ParaTemplate:Dagger	Template:Para
Template:Para	Template:Para
Template:ParaTemplate:Dagger	Template:Para, Template:Para, Template:Para + Template:Para
Template:Dagger Parameters checked for this error may also have the enumerated forms: Template:Para or Template:Para etc.

This error occurs when any of these Template:Para parameters contain a wikilink or a URL, or they contain any of the characters not permitted in Wikipedia article titles per WP:TITLESPECIALCHARACTERS (except _ (underscore), used as a replacement for spaces, and #, used as a fragment identifier when linking to article sections). The prohibited characters are: < > [ ] | { }.

The Template:Para parameter value should contain only the title of a Wikipedia article or a link to a section of a Wikipedia article. Module:Citation/CS1 checks the Template:Para parameter values for wikimarkup and for a URI scheme (http://, https://, the protocol relative scheme //, etc.). Interlanguage links in any of the Template:Para parameters require a leading colon:

:fr:Période d'exil de Caravage

While primarily intended to catch the errors mentioned above, Module:Citation/CS1 will also catch malformed interlanguage wikilinks wherever they occur. Interlanguage wikilinks that have the form:

[[fr:Période d'exil de Caravage]]

do not create visible clickable links in the article text. Instead, these links appear in the left pane in the languages list. Module:Citation/CS1 disables interlanguage links in this form and emits an error message. The correct form is:

[[:fr:Période d'exil de Caravage]]

This error can also be caused when:

• there is a Template:Para value and the matching Template:Para parameter contains a wikilink.
• Template:Para and Template:Para (and enumerated forms) contain a wikilink

To resolve this error, do one of the following:

• Ensure that the Template:Para value is the full name of a Wikipedia article (without brackets) or a section of an article, and not a link to an external web site.
• Make sure that there are no wikilinks in the matching Template:Para parameters.
• If you want to link to a URL outside of Wikipedia, move the link to Template:Para or a similar parameter, if one is available in the template you are using.

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Check |pmc= value

<section begin="bad_pmc_help_text" />Template:Help desk

The Template:Para parameter is for the PubMed Central identifier. PMCs are sequential numbers beginning at 1 and counting up. Module:Citation/CS1 checks the PMC identifier to make sure that the value is a number greater than zero and less than and that the identifier contains only digits. Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct, and that there are no letters, punctuation, or other characters. Do not include "PMC" in the value.

If the value is correct and larger than the currently configured limit of , please report this at Help talk:Citation Style 1, so that the limit can be updated.

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Check |pmid= value

<section begin="bad_pmid_help_text" />Template:Help desk

The Template:Para parameter is for the PubMed identifier. PMIDs are checked to ensure that the identifier is a simple number without punctuation or spaces with a value between 1 and . Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct. If you find something that looks like a PMID and begins with "PMC", use Template:Para instead of Template:Para.

If the value is correct and larger than the currently configured limit of , please report this at Help talk:Citation Style 1, so that the limit can be updated.

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Check |rfc= value

<section begin="bad_rfc_help_text" />Template:Help desk

The Template:Para parameter is for the Internet Engineering Task Force (IETF) RFC identifier (unrelated to Wikipedia's internal RfCs). IETF RFCs are checked to ensure that the identifier is a simple number without punctuation or spaces with a value between 1 and . Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct.

If the value is correct and larger than the currently configured limit of , please report this at Help talk:Citation Style 1, so that the limit can be updated.

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Check |sbn= value

<section begin="bad_sbn_help_text" />Template:Help desk

Citation Style 1 and Template:Cs2 templates that contain Template:Para are checked to ensure that the SBN is the proper length (nine digits), that the SBN uses the correct optional separators (simple space or hyphen), and that the final check digit is correct according to the SBN specification. Only one SBN is allowed in this field because the whole Template:Para value is included in the citation's COinS metadata. See also Wikipedia:COinS. More than one SBN, or characters that are not part of the SBN, corrupt the COinS metadata and may also corrupt the link to Special:BookSources.

The error message <type> indicator can be:

– SBN is not 9 digits

– SBN has one or more incorrect digits; look for typos and transposition

– SBN has one or more 'digits' that is not in the allowed set

– mis-positioned 'X' check digit

To resolve this error, ensure that the Template:Para value is correct, that only one SBN is used, that the proper optional separators are used, and that no other text is included. If the check digit is a lowercase 'x', change it to an uppercase 'X'.

• Do not try to resolve the error by simply recalculating the check digit. The check digit is there to check whether the main part of the number is correct. If the SBN is failing to validate, it is likely that there is a typo in the main part of the number. In this case, recalculating the check digit results in an apparently valid ISBN that leads to the wrong source (or to nowhere).
• If the SBN as printed in your source is refusing to validate, do check both the front matter and the book cover for SBNs. It is not uncommon for the SBN to be misprinted in the front matter but correct on the cover.
• Do preview your edit and check that the new SBN does now link to the correct source.

In very rare cases, publishers have released books with malformed SBNs. If you are certain that a non-conforming SBN truly corresponds to the published work, then you can add accept-this-as-written markup around the identifier to suppress the error message. In many cases, books may have been reissued with a corrected SBN. Use a corrected SBN when possible.

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Check |ssrn= value

<section begin="bad_ssrn_help_text" />Template:Help desk

The Template:Para parameter is for the Social Science Research Network identifier. SSRNs are checked to ensure that the identifier is a simple number without punctuation or spaces with a value between 100 and . Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct.

If the value is correct and larger than the currently configured limit of , please report this at Help talk:Citation Style 1, so that the limit can be updated.

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Check |s2cid= value

<section begin="bad_s2cid_help_text" />Template:Help desk

The Template:Para parameter is for the Semantic Scholar corpus identifier. S2CIDs are checked to ensure that the identifier is a simple number without punctuation or spaces with a value between 1 and . Further validation is not performed.

To resolve this error, ensure that the Template:Para value is correct.

If the value is correct and larger than the currently configured limit of , please report this at Help talk:Citation Style 1, so that the limit can be updated.

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Check |url= value

<section begin="bad_url_help_text" />Template:Help deskTemplate:Plainlist

External links in Citation Style 1 and Template:Cs2 templates are made from two parts: the title (Template:Para, Template:Para, etc.) and the URL (Template:Para, Template:Para, Template:Para, etc.). The Template:Para parameter and other URL parameters must begin with a supported URI scheme. The URI schemes http://, https://, and the protocol relative scheme // are most commonly used; irc://, ircs://, ftp://, news:, mailto: and gopher:// are also supported.

The URL scheme and host are checked to ensure that they contain only Latin characters, certain (required) punctuation, and do not contain spaces. The URL may be protocol relative (begins with //). If there are no spaces and the URL is not protocol relative, then the scheme must comply with RFC 3986.

Some URL domains are written with non-Latin characters. cs1|2 does not accept those kinds of URLs so they must be 'internationalized'. Online tools are available to internationalize URLs that are written in non-Latin scripts:

• Template:Cite web Only enter the domain in the tool and not the full url.

Top- and second-level domain names are checked for proper form. Generally, top-level domain names must be two or more letters; second-level domain names must be two or more letters, digits, or hyphens (first and last character must be a letter or digit). Single-letter second-level domains are supported for:

• all cc TLDs (the country code is not validated)
• the .org TLD
• certain letters of the .com TLD (q, x, z)
• certain letters of the .net TLD (i, q)
• certain other TLDs ()

Third- and subsequent-level domain names are not checked. The path portion of the URL is not checked.

There is an additional test for Template:Para. The cs1|2 templates expect that Template:Para will hold a unique URL for an archived snapshot of the source identified by Template:Para or Template:Para (or any of its aliases). This error message is emitted when the value assigned to Template:Para is the same as the matching title or chapter URL.

To resolve this error, ensure that:

• Template:Para and other URL parameters contain valid URLs
• URLs copy-pasted from elsewhere include the URI scheme
• that the domain name uses only Latin characters

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Check |zbl= value

<section begin="bad_zbl_help_text" />Template:Help desk

When Citation Style 1 and Template:Cs2 templates contain Template:Para, a test is done to see if the Zbl identifier value looks like a properly defined value. The Template:Para identifier is checked to make sure that it has the form: nnnn.nnnnn where n is any digit 0–9. Up to three leading zeros in the first quartet may be omitted. Further validation of the Zbl identifier is not performed.

To resolve this error, ensure that the Template:Para value is correct.

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Cite has empty unknown parameter: <param>

<section begin="param_unknown_empty_help_text" />Template:Help deskTemplate:Plainlist

This error message highlights CS1|2 templates that hold empty parameters with names that are not known to a given CS1|2 template. This error message is a companion to Unknown parameter |xxxx= ignored.

Empty positional parameters, which typically look like two adjacent pipes in a template, | |, or a pipe and then the end of the template, |}}, are identified as numbered parameters: Template:Error-small. Similarly, a pipe followed by an HTML comment that encloses everything before the next pipe or closing brace, | <!--<param name/value pair>--> | will be identified as an empty numbered parameter. Parameters that have both a pipe and an equal sign but do not have a name are identified as empty-string parameters: |= or | = → Template:Error-small. Various templates that wrap CS1|2 templates may cause this error when they use constructs like this: <syntaxhighlight lang="wikitext" inline>|=</syntaxhighlight>. When {{{2|}}} does not have a value, the template creates |=.

To resolve this error:

• remove the extra pipe,
• correct the parameter name,
• remove the parameter from the CS1|2 template, or
• change the citation to use a more appropriate template (e.g. change Template:Tl to Template:Tl)

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Cite document requires |publisher=

<section begin="missing_publisher_help_text" />Template:Help desk

This error message is displayed when Template:Tlx does not have Template:Para. Usually, there is a more appropriate template that can be used in place of

1. REDIRECT Template:Template link code. When
2. REDIRECT Template:Template link code is used, it accepts a limited subset of the cs1|2 parameter suite but requires Template:Para.

To resolve this error, use a more appropriate template (preferred solution) or provide Template:Para.

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Cite <template> requires |<param>=

<section begin="missing_periodical_help_text" />Template:Help desk

These CS1 periodical templates require a periodical parameter. The periodical templates are:

Template:Tlx

Template:Tlx

The error message suggests a periodical parameter that matches the template, but there is no requirement to use the suggested parameter; any one of these periodical parameters may be used:

• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para

In some cases, an incorrect template has been used (e.g. Template:Tlx for a web page, book, or standalone document). The appropriate resolution in these cases is to change the incorrect template to Template:Tlx, Template:Tlx, Template:Tlx, or a different, more appropriate template.

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Cite uses deprecated parameter |<param>=

<section begin="deprecated_params_help_text" />Template:Help desk

Over time, some parameters have become obsolete or unnecessary. When this happens, the parameters are identified as deprecated. Editors are encouraged to use other parameters that accomplish the same purpose as those that have been deprecated. The CS1|2 deprecated parameters are listed in the following table, along with recommended replacement parameters. Parameter names are case-sensitive. Editors should expect that support for deprecated parameters will soon be withdrawn.

To resolve this error, use a supported parameter.

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Deprecated CS1/CS2 parameters

Deprecated parameter	Replace with	Date
none deprecated at present

<section end="deprecated_params_table" /><section end="deprecated_params_help_text" /><section begin="deleted_params_table" />

Recently removed CS1/CS2 parameters

Removed parameter	Replace with	Date	Note
Template:Para	Template:Para / Template:Para, Template:Para, Template:Para	August 2024

<section end="deleted_params_table" />

Cite uses generic name

<section begin="generic_name_help_text" />Template:Help desk

Articles are listed in this category when Module:Citation/CS1 identifies template author or editor name parameters that use place-holder names. Such names may have been provided by bots or other tools that are unable to identify the source's correct names. Pages in this category should only be added by Module:Citation/CS1.

CS1|2 maintains a short list of 'names' that are typically not the correct names for the cited source. Some examples are:

• about us
• author
• collaborator
• contributor
• contact us
• directory
• editor
• email
• facebook
• google
• home page
• instagram
• interviewer
• linkedIn
• pinterest
• policy
• privacy
• site name
• statement
• submitted
• super user
• translator
• tumblr
• twitter
• user
• verfasser

If you are aware of other common place-holder names, please report them at Help talk:Citation Style 1, so that they can be added to the list.

To resolve this error, replace the place-holder name with the source's actual author or editor name, or use a more appropriate parameter.

Example fixes:

• Replace Template:Para with Template:Para

False positives are possible. When the name is valid, wrap the parameter value in the accept-this-as-written markup:

Template:Para

Please do not use this markup when it is not appropriate.

Pages with this error are automatically placed in .

See also the error category Category:CS1 errors: generic title.<section end="generic_name_help_text" />

Cite uses generic title

<section begin="generic_title_help_text" />Template:Help desk

Articles are listed in this category when Module:Citation/CS1 identifies template Template:Para parameters that use place-holder titles. Such titles may have been provided by bots or other tools that are unable to identify the source's correct title. Pages in this category should only be added by Module:Citation/CS1.

CS1|2 maintains a short list of 'titles' that are typically not the title of the cited source. Some examples are: Template:Div col begin

• 404
• are you a robot
• hugedomains.com
• internet archive wayback machine
• log into facebook
• login • instagram
• no title – various forms
• page not found
• redirecting...
• subscribe to read
• unknown – various forms
• usurped title
• wayback machine
• webcite query result
• website is for sale
• wikiwix's cache

If you are aware of other common place-holder titles, please report them at Help talk:Citation Style 1, so that they can be added to the list.

To resolve this error, replace the place-holder title with the source's actual title.

False positives are possible. When the name is valid, wrap the parameter value in the accept-this-as-written markup:

Template:Para

Please do not use this markup when it is not appropriate.

Pages with this error are automatically placed in .

See also the maintenance category Category:CS1 maint: archived copy as title and the similar error category Category:CS1 errors: generic name.<section end="generic_title_help_text" />

|citeseerx= required

<section begin="citeseerx_missing_help_text" />Template:Help desk

Template:Tlx requires the identifier parameter Template:Para.

To resolve this error, ensure that the template has Template:Para with a properly constructed value.

Pages with this error are automatically placed in .<section end="citeseerx_missing_help_text" />

|class= ignored

<section begin="class_ignored_help_text" />Template:Help desk

Only used in Template:Tlx templates, Template:Para is only appropriate when the template uses Template:Para or Template:Para identifier formats; see Cite arXiv §Usage.

To resolve this error, remove Template:Para.

Pages with this error are automatically placed in .<section end="class_ignored_help_text" />

|contributor= ignored

<section begin="contributor_ignored_help_text" />Template:Help desk

Only used in book citations, Template:Para identifies the author of a contribution, typically an afterword, foreword, introduction, preface, etc., to another (primary) author's work. This error occurs when Template:Para is used in a template that is not Template:Tlx or Template:Tlx or is one of these two templates and one of the Template:Para parameter aliases is set.

To resolve this error, consider the Template:Para parameter, choose a more appropriate CS1 or CS2 template or remove Template:Para.

Pages with this error are automatically placed in .<section end="contributor_ignored_help_text" />

|contributor= requires |<param>=

<section begin="contributor_missing_required_param_help_text" />Template:Help deskTemplate:Plainlist

Only used in book citations, Template:Para identifies the author of a contribution, typically an afterword, foreword, introduction, preface, etc., to another (primary) author's work. As such, the primary author is required (Template:Para or appropriate alias) as is the title of the contribution (Template:Para).

To resolve this error, include the book's primary author in Template:Para, or Template:Para, Template:Para, or Template:Para and include the contribution title in Template:Para; or consider the Template:Para parameter or remove Template:Para.

Pages with this error are automatically placed in .<section end="contributor_missing_required_param_help_text" />

|doi-broken-date= requires |doi=

<section begin="doibroken_missing_doi_help_text" />Template:Help desk

When Template:Para is used in a CS1|2 template, Template:Para (with value) must also be present.

To resolve this error, either add the missing DOI or remove the 'broken' parameter.

Pages with this error are automatically placed in .<section end="doibroken_missing_doi_help_text" />

|edition= has extra text

<section begin="extra_text_edition_help_text" />Template:Help desk

The templates are responsible for static text rendered in the citation. When Template:Para is used in a template, cs1|2 adds the abbreviation 'ed.' to the value in the parameter so:

Template:Para

renders as:

1st ed.

The templates emit this error message when various forms of ed, edn, or edition are found in the value assigned to Template:Para.

To resolve this error, remove the extraneous text from the parameter value.

Pages with this error are automatically placed in .<section end="extra_text_edition_help_text" />

Empty citation

<section begin="empty_citation_help_text" />Template:Help desk

A Citation Style 1 or Template:Cs2 template marked as "Empty" contains no recognizable parameter identifiers. For example, this citation is marked as "empty" even though it contains usable information:

{{cite web |http://www.foobar.com |The Foobar News}}

The citation is "empty" because it does not contain the necessary parameter identifiers (in this case Template:Para and Template:Para) that tell Template:Tlx how to use the information that the citation contains.

A citation is also marked as "empty" when it contains only parameters that it doesn't recognize:

{{cite book |titolo=The Bazquux Uprising |anno=2015}}

This citation is "empty" because the Italian-language parameters Template:Para and Template:Para are not recognized as valid parameter names on the English Wikipedia.

"Empty citation" may also mean that an editor meant to use another template entirely. Perhaps the editor used Template:Tlx when the intent was to use Template:Tlx or Template:Tlx.

To resolve this error, add appropriate parameter identifiers, translate foreign language parameter names to their English equivalents, or replace the CS1/CS2 template with a more appropriate template.

Pages with this error are automatically placed in .<section end="empty_citation_help_text" />

Explicit use of et al.

<section begin="explicit_etal_help_text" />Template:Help desk

This error occurs where a Citation Style 1 or Template:Cs2 template detects that one of the names parameters contains some form of "et al." either as a separate name parameter (Template:Para) or as a suffix added to a name list (Template:Para) or first name (Template:Para).

This error can occur in any of the author, editor, interviewer, translator, or contributor parameters.

Use the Template:Para parameter instead (or other applicable Template:Para parameter), as documented at Help:Citation Style 1#Display options.

Pages with this error are automatically placed in .<section end="explicit_etal_help_text" />

External link in |<param>=

<section begin="param_has_ext_link_help_text" />Template:Help desk

This error occurs when a URL is found in any parameter that is not one of these URL-holding parameters: Template:Div col begin

• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para

or any of these insource locator parameters: Template:Div col begin

• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para

To resolve this error, remove the external link from the identified parameter. Consider placing the external link in a more appropriate parameter:

• for Template:Para, the URL may belong in Template:Para.
• for other parameters, it may belong in Template:Para.

Wrapping the parameter value in double parentheses (i.e. "accept as written" markup) does not work around this error message.

Pages with this error are automatically placed in .<section end="param_has_ext_link_help_text" />

|<first>n= missing |<last>n=

<section begin="first_missing_last_help_text" />Template:Help desk

Citation Style 1 and Template:Cs2 templates requires a Template:Para parameter for each Template:Para parameter in a citation. Author, contributor, editor, interviewer, and translator lists are checked for proper last/first pairing. CS1|2 will emit this error message for the first mismatch it detects. If there are more last/first mismatches in a citation, subsequent mismatches are not detected.

There is no requirement that each Template:Para have a matching Template:Para.

To resolve this error, ensure that each Template:Para has a corresponding Template:Para.

Pages with this error are automatically placed in .<section end="first_missing_last_help_text" />

|format= requires |url=

<section begin="format_missing_url_help_text" />Template:Help deskTemplate:Plainlist

These errors occur when Citation Style 1 and Template:Cs2 templates use Template:Para or Template:Para without also providing a corresponding URL for Template:Para or Template:Para, respectively. The Template:Para and Template:Para parameters are used to specify the file format of a web resource, such as PDF, DOC, or XLS. In some cases an editor may have intended to use Template:Para to specify a kind of document, such as hard cover, paperback, or pamphlet. The Template:Para and Template:Para value is always displayed.

The list of Template:Para parameters is:

Template:Para, Template:Para, Template:Para, Template:Para, Template:Para, Template:Para, Template:Para, Template:Para, Template:Para, Template:Para

(Citations that relied on the pre-2014, somewhat odd use of Template:Para and Template:Para may need adjustment in regard to Template:Para.)

To resolve this error, remove Template:Para or Template:Para; define Template:Para or Template:Para; or change Template:Para to Template:Para (or to Template:Para if Template:Para is used without Template:Para.

Pages with this error are automatically placed in .<section end="format_missing_url_help_text" />

Invalid |display-<names>=<value>

<section begin="disp_name_help_text" />Template:Help desk

These error messages are emitted when Module:Citation/CS1 identifies citations that use one or more of the Template:Para parameters with an invalid assigned <value>. An invalid assigned <value> is a number that is greater than or equal to the number of <names> in the associated name-list or it is non-numeric text that Module:Citation/CS1 cannot recognize as a form of the keyword etal.

To resolve this error, do one of the following:

• Remove the Template:Para parameter from the citation (typically because "et al." is not appropriate in the citation)
• Change the <value> of the Template:Para parameter such that it is less than the number of <names> in the name-list (thereby truncating the displayed list to the number)
• Change the <value> of the Template:Para parameter to etal, which will cause "et al" to display after the last <name>.

Pages with this error are automatically placed in .<section end="disp_name_help_text" />

Invalid <param>=<value>

<section begin="invalid_param_val_help_text" />Template:Help desk

To function properly, some parameters are limited to a certain set of acceptable values. This error message indicates that a parameter has been assigned a value that is not a member of the parameter's defined set of acceptable values.

Letters in values must all be in lower case, as shown below.

Parameters with limited acceptable values

Parameter	Acceptable values
Template:Para	dmy, dmy-all, mdy, mdy-all, ymd, ymd-all
Template:Para	cs1, cs2
Template:Para	amp, ampersand, and, &, serial, vanc
Template:Para	true, y, yes
Template:Para
Template:Para	free
Template:Para
Template:Para
Template:Para
Template:Para
Template:Para
Template:Para
Template:Para
Template:Para	subscription, registration, limited
Template:Para
Template:Para
Template:Para
Template:Para
Template:Para
Template:Para
Template:Para	dead, live, deviated, unfit, usurped

To resolve this error for the parameters in the table, use an appropriate value.

Support for Template:Para is withdrawn because cs1|2 templates now automatically create the CITEREF anchor value that Template:Para controlled. To resolve this error, remove Template:Para.

Pages with this error are automatically placed in .<section end="invalid_param_val_help_text" />

Invalid |script-<param>=: <type>

<section begin="script_parameter_help_text" />Template:Help desk

The various Template:Para parameters are checked for proper form. When an error is detected, the error message briefly identifies the type of the error:

– the Template:Para parameter has a language-code prefix but is otherwise empty

– the Template:Para parameter has text but is missing the required language-code prefix; the prefix has the form xx: or xxx: where xx or xxx is a valid ISO 639-1 or ISO 639-3 language code known to CS1|2 as a language that uses a non-Latin script; the colon (:) is required

– the Template:Para parameter has a (possibly valid) language code that CS1|2 does not recognize as a language using a non-Latin script

Language codes known to CS1|2 for languages that do not use a Latin script are:

Pages with this error are automatically placed in .<section end="script_parameter_help_text" />

ISBN / Date incompatibility

<section begin="invalid_isbn_date_help_text" />Template:Help desk – this error message hidden by default

ISBNs were created c. 1965. Books published before that date will not have been issued an ISBN.

To resolve this error:

remove the ISBN when citing a source published before 1965

if the edition of the cited book was published after 1965, ensure that Template:Para or Template:Para has the correct publication year.

adding Template:Para may be appropriate in such cases; e.g., Template:Para

Pages with this error are automatically placed in .<section end="invalid_isbn_date_help_text" />

|issue=/|number= has extra text

<section begin="extra_text_issue_help_text" />Template:Help desk

The templates are responsible for static text rendered in the citation. When Template:Para or Template:Para is used in a template, cs1|2 formats the issue number according to the style corresponding with the publication type associated with the used citation template.

The templates emit this error message when various forms of issue or number prefixes (like Iss. or No.) are found in the value assigned to Template:Para or Template:Para.

To resolve this error, remove the extraneous text from the parameter value. If the extraneous text removed is related to issues, please use the Template:Para parameter rather than Template:Para for this, and vice versa. At present, the output is the same for both parameters, but this may not hold true in future versions, therefore it is important that issues and number values are used with the proper parameter as per what nomenclature is used in the actual publication.

Pages with this error are automatically placed in .<section end="extra_text_issue_help_text" />

Italic or bold markup not allowed in: |<param>=

<section begin="apostrophe_markup_help_text" />Template:Help desk

Italic ('') or bold (''') wikimarkup is not allowed in publisher and periodical parameters. These parameters include:

• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para
• Template:Para

To resolve this error, remove wiki markup from the named parameter's value and ensure that the template is using the correct parameters; when citing a newspaper, use Template:Para for the newspaper's name, not Template:Para, etc.

Pages with this error are automatically placed in .<section end="apostrophe_markup_help_text" />

|medrxiv= required

<section begin="medrxiv_missing_help_text" />Template:Help desk

Template:Tlx requires the identifier parameter Template:Para.

To resolve this error, ensure that the template has Template:Para with a properly constructed value.

Pages with this error are automatically placed in .<section end="medrxiv_missing_help_text" />

Missing |<name>n=

<section begin="missing_name_help_text" />Template:Help desk

So that all names are listed in a rendered citation, Citation Style 1 and Template:Cs2 templates require n in Template:Para (and its aliases) to increment by 1 for each name in the list (author, contributor, editor, interviewer, translator). This error message is emitted when there is a 'hole' in the numbering (an author list made up of Template:Para and Template:Para but without Template:Para for example).

The test will not detect a 'hole' that is larger than 1. It is presumed that when Template:Para and Template:Para are both not present, then the test has reached the end of the list.

To resolve this error, ensure that the numbering of the Template:Para parameters increments properly.

Pages with this error are automatically placed in .<section end="missing_name_help_text" />

Missing or empty |title=

There are two slightly different error conditions that can arise when CS1 citations lack appropriate titles. In each case, CS1 reports this error message. The necessary resolution may vary depending on the cause of the error. The error message links to the appropriate description below.

Bare URL without a title

<section begin="bare_url_missing_title_help_text" />Template:Help desk

All Citation Style 1 and Template:Cs2 templates report this error when one of the URL-containing parameters cannot be paired with an associated title. This error may also occur when Template:Para cannot be linked with Template:Para because the citation also contains a conflicting Template:Para parameter.

URL-containing parameters and associated title parameters

URL parameters	Title parameters
Template:Para	Template:Para
Template:Para	Template:Para, Template:Para, Template:Para, Template:Para, Template:Para
Template:Para	Template:Para, Template:Para, Template:Para, Template:Para, Template:Para
Template:Para	Template:Para, Template:Para
Template:Para	Template:Para, Template:Para, Template:Para, Template:Para, Template:Para
Template:Para	Template:Para, Template:Para, Template:Para, Template:Para, Template:Para
Template:Para	Template:Para, Template:Para
Template:Para	Template:Para
Template:Para	Template:Para, Template:Para, Template:Para, Template:Para, Template:Para
Template:Para	Template:Para
Template:Para	Template:Para

A unique case exists for Template:Tl: if Template:Para or Template:Para has a value, Template:Para is omitted or empty, and Template:Para does not point to an article, then Template:Para is automatically linked with the same URL as the PMC or DOI. This default behaviour can be overridden using Template:Para.

Because URLs are ugly and generally uninformative, it is expected that editors should provide a meaningful title for each URL. In most cases this can be accomplished by using the Template:Para parameter.

To resolve this error, provide an appropriate title for the URL-containing parameter. In the case where Template:Para and Template:Para are contending for Template:Para you must choose which one to keep. Consider moving Template:Para or Template:Para to a more suitable parameter.

Pages with this error are automatically placed in .<section end="bare_url_missing_title_help_text" />

Citation without a title of any form

<section begin="citation_missing_title_help_text" />Template:Help deskTemplate:Plainlist

This error occurs for Citation Style 1 and Template:Cs2 templates when all of Template:Para, Template:Para, and Template:Para are omitted or left blank. At least one of these title parameters must be provided for each citation.

Template:Tlx will show this error if Template:Para is omitted or left blank (even if a Template:Para is provided).

Template:Tlx will show this error if Template:Para has a value but Template:Para (or another Template:Para alias) is omitted or left blank.

Sometimes this error occurs because an editor has used a CS1|2 citation as a shortened footnote when Template:Tlx or one of the Template:Tlx family of templates would have been more appropriate. This error also occurs when an editor used Template:Tlx but intended to use Template:Tlx.

To resolve this error, provide a value for Template:Para, Template:Para, and/or Template:Para or replace the CS1|2 template with a more appropriate template. If you are listing a periodical or an issue of a periodical in a bibliography rather than within Template:Tag tags, Template:Tlx may be more appropriate.

Pages with this error are automatically placed in .<section end="citation_missing_title_help_text" />

Missing or empty |url=

<section begin="cite_web_url_help_text" />Template:Help desk

This error message is reported by Template:Tlx, Template:Tlx, and Template:Tlx when the template parameters Template:Para and Template:Para are both missing, blank or not properly entered. Note that Template:Para or Template:Para is the name of the site, not the URL.

To resolve this error, provide a value for Template:Para or use a more appropriate template such as Template:Tl, Template:Tl or other Citation Style 1 or Template:Cs2 template.

Pages with this error are automatically placed in .<section end="cite_web_url_help_text" />

Missing pipe

<section begin="missing_pipe_help_text" />Template:Help desk

Citation Style 1 and Template:Cs2 templates report this error when one parameter has text that looks like it is a parameter missing a pipe (|). This error occurs when a template parameter value contains characters and digits followed by an equal sign. If the alphanumeric text immediately preceding the equal sign is a valid CS1|2 parameter name, the module assumes that the template is missing a pipe and emits this error message.

Some legitimate titles will contain a CS1|2 parameter name followed by an equal sign. In that case, enclose the equal sign in nowiki tags, like this: Template:Tag. For most other cases, simply add the missing pipe.

Pages with this error are automatically placed in .<section end="missing_pipe_help_text" />

More than one of |<param1>=, |<param2>=, and |<param3>= specified

<section begin="redundant_parameters_help_text" />Template:Help desk

This error occurs when a Citation Style 1 or Template:Cs2 template includes more than one parameter that maps to the same meaning. For example, Template:Para, Template:Para, and Template:Para are all synonyms of each other, so no more than one of these parameters should ever be used in a single template.

To resolve this error, remove or modify the redundant parameter(s).

This error occurs when a CS1 or CS2 template uses more than one type of author or editor name-list style. There are three kinds of incompatible author-name-list styles:

Template:Para and Template:Para / Template:Para (and their various aliases), Template:Para, and Template:Para

and similarly, three editor-name-list styles:

Template:Para and Template:Para / Template:Para (and their various aliases) as well as Template:Para

To resolve this error, choose one name-list-style. Use the chosen style for both of the author and editor name-lists.

Pages with these errors are automatically placed in .<section end="redundant_parameters_help_text" />

|page(s)= has extra text

<section begin="extra_text_pages_help_text" />Template:Help desk

The templates are responsible for static text rendered in the citation. When Template:Para/Template:Para, Template:Para/Template:Para, Template:Para or Template:Para is used in a template, cs1|2 inserts the appropriate pagination prefix 'p.' or 'pp.' ahead of the value in the parameter so:

Template:Para

renders as:

p. 123

and:

Template:Para

renders as:

pp. 123–125

The templates emit this error message when various forms of p, pp, pg, pgs, page, or pages are found in the value assigned to Template:Para/Template:Para, Template:Para/Template:Para, Template:Para or Template:Para.

To resolve this error, remove the extraneous text from the parameter value.

Pages with this error are automatically placed in .<section end="extra_text_pages_help_text" />

|<param>-access= requires |<param>=

<section begin="param_access_requires_param_help_text" />Template:Help desk

This error is reported when an access level has been specified for some external link, but the corresponding required parameter is missing or empty. The parameter can be one of

Access-level specifier required parameter

Specifier	Required parameter
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para
Template:Para	Template:Para

To resolve this error, either provide a value for the parameter, or remove the access level specification.

Pages with this error are automatically placed in .<section end="param_access_requires_param_help_text" />

|<param>= has numeric name

<section begin="numeric_names_help_text" />Template:Help desk

This error is reported when a name-list parameter Template:Para, Template:Para, Template:Para, Template:Para, Template:Para (including aliases) has an assigned value that is composed solely of digits and / or punctuation. Errors of this type are often the result of automated or semi-automated edits where the source metadata is misplaced or improperly translated.

To resolve this error, make sure that the value assigned to the name-list parameter is a name and only a name.

Pages with this error are automatically placed in .<section end="numeric_names_help_text" />

|<periodical>= ignored

<section begin="periodical_ignored_help_text" />Template:Help desk

Citation Style 1 templates Template:Tlx and Template:Tlx do not support Template:Para (and aliases Template:Para, Template:Para, Template:Para, Template:Para, Template:Para) and associated Template:Para and Template:Para (and their aliases).

To resolve this error:

• use a more appropriate citation template, or
• most common: change Template:Para to Template:Para (or appropriate alias) and then change Template:Para to Template:Para, or
• change Template:Para to Template:Para if Template:Para is the actual title of the book and Template:Para contains the name of a book series, or
• change Template:Para to another appropriate parameter (it has been used to hold values for Template:Para, Template:Para, Template:Para, and more), or
• move the content of the Template:Para parameter out of the template, before the closing </ref>, or
• delete the Template:Para parameter

Pages with this error are automatically placed in .<section end="periodical_ignored_help_text" />

|pmc-embargo-date= requires |pmc=

<section begin="embargo_missing_pmc_help_text" />Template:Help desk

When Template:Para is used in a CS1|2 template, Template:Para (with value) must also be present.

To resolve this error, either add the missing PMC or remove the 'broken' parameter.

Pages with this error are automatically placed in .<section end="embargo_missing_pmc_help_text" />

|ssrn= required

<section begin="ssrn_missing_help_text" />Template:Help desk

Template:Tlx requires the identifier parameter Template:Para.

To resolve this error, ensure that the template has Template:Para with a properly constructed value.

Pages with this error are automatically placed in .<section end="ssrn_missing_help_text" />

Text "????" ignored

<section begin="text_ignored_help_text" />Template:Help desk

Unlike many Wikipedia templates, the Citation Style 1 and Template:Cs2 templates do not use unnamed or positional parameters. When a citation contains text between vertical bars and that text does not contain an equal sign (=), CS1|2 ignores the text and reports the error. This is true even when the text is the name of a valid parameter.

This error can also be caused by vertical bars (pipe characters) that are part of URLs or titles. When vertical bars occur in URLs, replace each vertical bar with %7C. When vertical bars occur in parameter values that are not URLs, replace each vertical bar with | or Template:Tl.

To resolve this error, remove the extraneous text, add '=', add an appropriate parameter name from the template you're using to complete the parameter, or properly encode vertical bars in URLs and titles.

Pages with this error are automatically placed in .<section end="text_ignored_help_text" />

|trans-<param>= requires |<param>= or |script-<param>=

<section begin="trans_missing_title_help_text" />Template:Help desk

Citation Style 1 and Template:Cs2 templates report this error when the citation has an English translation of the title in Template:Para or chapter title in Template:Para but does not have the original-language title in Template:Para or original-language chapter title in Template:Para.

To resolve this error, provide the original language title for Template:Para or chapter title for Template:Para. Consider adding Template:Para if not already part of the citation.

Pages with this error are automatically placed in .<section end="trans_missing_title_help_text" />

Unknown parameter |<param>= ignored

<section begin="parameter_ignored_help_text" />Template:Help deskTemplate:Plainlist

Citation Style 1 and Template:Cs2 templates report this error when the name portion of a parameter's Template:Para pair is not recognized as a valid name. Typically, this is caused by spelling or capitalization errors or when a page is reverted to a version where the citation template did support the parameter. It can also be caused by the use of parameters that are valid in some, but not all, CS1|2 templates. For example, Template:Tl citations are sometimes erroneously created using Template:Para and Template:Para when they should use Template:Para and Template:Para instead.

The CS1|2 engine does not ignore unrecognized parameters. The purpose of the citation is to properly identify the source, not to act as a repository of notes and ancillary information.

CS1|2 template parameters are lower case. CS1|2 will report this error when the parameter's name contains uppercase letters (Template:!xt) but the parameter's name is defined as lowercase (Template:Xt). Some identifier parameters, like Template:Para, Template:Para, Template:Para, etc., can be either lower case or upper case, but not of mixed case (Template:Para or Template:Para but not Template:Para). For common parameter misspellings, like Template:Para instead of Template:Para and some former template parameters, CS1|2 will suggest a valid parameter name. The list of deprecated and recently removed parameters may contain additional information as well.

Reported unknown parameters following a Template:Para scheme are created by Citation Bot when it finds duplicate parameters Template:Para in a template.

To resolve this error, replace the erroneous parameter name with a correct one, possibly using the suggested name. Ensure that the parameter's name is correctly spelled and that there are no characters except spaces between the parameter's name and the leading vertical bar (|) or trailing equals sign (=). A list of valid parameters can be found by consulting Help:Citation Style 1 or visiting the description page of the specific template being used, such as Template:Tlx, Template:Tlx, Template:Tlx, etc. Consider moving information associated with the unknown parameter into an appropriate parameter or to a section of the article's talk page for preservation.

Pages with this error are automatically placed in .<section end="parameter_ignored_help_text" />

URL–wikilink conflict

<section begin="wikilink_in_url_help_text" />Template:Help desk

External links in a rendered citation are a combination of url-holding parameters, Template:Para, Template:Para, etc., with title-holding parameters, Template:Para, Template:Para, etc. Title-holding parameters may be wikilinked to another Wikipedia article but not when there is a matching url-holding parameter in the citation. When this condition occurs, the wikilink is suppressed, the wiki markup ignored, and the rendered citation links to the external site.

With Template:Tlx, auto-linking of the Template:Para or Template:Para parameter value can cause this condition to occur implicitly without a specific url-holding parameter.

Some templates will also cause this error if they are part of a title-holding parameter. The error occurs when the template produces wikilinked content. For example, Template:Tlx templates output a wikilinked category. Templates in title-holding parameters may also corrupt the citation's COinS metadata. As a general rule, avoid using templates in title-holding parameters unless you know that the template's effects are entirely visual (Template:Tlx and the like).

This type of error may also occur in identifier-based templates (Template:Tlx, etc.). When this happens, the error message is shown in the article but the error is actually located in the identifier-based citation template.

To resolve this error, remove wikilinks from title-holding parameters that are intended to be externally linked or remove the external URL, which will allow the internal wikilinks to work as expected. If the conflict is implicitly caused through auto-linking (see above), this can be disabled using Template:Para. If wikilink-producing templates are important to the citation, move them out of the CS1 template but leave them inside the citation's Template:Tag tags. Some of the functionality provided by templates may also be available through CS1 parameters.

To resolve errors in identifier-based citation templates, the template must be edited to correct the error. Exercise caution when editing these templates because identifier-based citation templates are often used in multiple articles.

Pages with this error are automatically placed in .<section end="wikilink_in_url_help_text" />

Vancouver style error

<section begin="vancouver_help_text" />Template:Help desk

This error is reported for citations that use Template:Para, Template:Para, Template:Para.

Vancouver style restricts author or editor names to the Latin alphabet. For the purposes of this test, Module:Citation/CS1 defines the Latin alphabet as the letters defined in the Unicode Latin character sets:

C0 Controls and Basic Latin (0041–005A, 0061–007A)

C1 Controls and Latin-1 Supplement (00C0–00D6, 00D8–00F6, 00F8–00FF)

Latin Extended-A (0100–017F)

Latin Extended-B (0180–01BF, 01C4–024F)

Latin Extended Additional (1E00–1EFF)

This error is also reported when more than two initials are used: in case of more than two initials, list only the first two.

This error is also reported when a corporate or institutional author is listed in Template:Para without proper delimiters. Corporate authors should be listed this way:

Template:Para

While normally correct, sometimes the names listed on a PMID page contain errors when the author surname has a lowercase nobiliary particle. For example, Template:PMID lists Magnus von Knebel Doeberitz as Doeberitz Mv which is not correct. This author's name should be listed as Template:Para.

Certain punctuation will be flagged as an error. For example, Unicode U+2019, right single quotation mark, causes an error because it is not a member of the Latin character sets identified above: Template:Para. Replace this character with the straight (or typewriter) apostrophe: Template:Para.

To resolve this error, Romanize author and editor names. Romanizing can result in two-letter initials, for example, the Greek letter 'Θ' Romanizes to 'Th'. When author names have this kind of initial, Module:Citation/CS1 can't know if this kind of initial is a typo or a legitimate Romanized character so it will emit the Vancouver error. To suppress the error after determining that the two-character initial is correct and not a typo, treat the name as if it were a corporate name by wrapping it in doubled parentheses: Template:Para → Template:Para

Similarly, Chinese hyphenated given names may appear in PubMed listings. For example: 'Wang Hsien-yu' may be listed on PubMed as 'Wang Hy' which will result in a Vancouver error. When this occurs, and upon verification that such names are correct, wrap them in doubled parentheses.

Specific rules for names:

• Surnames with hyphens and other punctuation in them
• Other surname rules
• Given names containing punctuation, a prefix, a preposition, or particle
• Degrees, titles, and honors before or after a personal name
• Designations of rank within a family, such as Jr and III
• Names appearing in non-roman alphabets (Cyrillic, Greek, Arabic, Hebrew, Korean) or character-based languages (Chinese, Japanese)
• Organizations as author
  • CS1|2 does not obey the semicolon-as-separator rule. Separate corporate and organizational names from each other and from individual names with a comma; wrap corporate and organizational names in doubled parentheses as described above.

Pages with this error are automatically placed in .<section end="vancouver_help_text" />

|volume= has extra text

<section begin="extra_text_volume_help_text" />Template:Help desk

The templates are responsible for static text rendered in the citation. When Template:Para is used in a template, cs1|2 formats the volume value according to the style corresponding with the publication type associated with the used citation template.

The templates emit this error message when some form of the word "volume" ("volume", "vol.") is found in the value assigned to Template:Para.

To resolve this error, remove the extraneous text from the parameter value.

Pages with this error are automatically placed in .<section end="extra_text_volume_help_text" />

Wikipedia Library link in <param>

<section begin="twl_url_help_text" />Template:Help desk

This error is reported when a URL-holding parameter has a URL that links to The Wikipedia Library. These urls include this text:

wikipedialibrary.idm.oclc.org

When these sorts of URLs are encountered, Module:Citation/CS1 emits this error message and automatically sets Template:Para because these URLs are not accessible by readers.

To resolve this error, make sure that the value assigned to the URL parameter is not the Wikipedia Library URL but is the URL of the source.

Pages with this error are automatically placed in .<section end="twl_url_help_text" />

#invoke:Cite errors

<section begin="module_cite_help_text" />Template:Help desk missing template name as first positional parameter

Module:Cite requires as its first positional parameter the canonical name of one of the cs1 templates (without the cite prefix) or the name of the cs2 template (citation). The module emits this error message when the first positional parameter is missing or empty.

unknown template name: <template name>

The module emits this error message when the first positional parameter is not the canonical name of a recognized cs1|2 template.

To resolve either of these errors, make sure that the module call has one of these canonical template names as its first positional parameter value:

• arxiv
• av media
• av media notes
• biorxiv
• book
• citation
• citeseerx
• conference
• document
• encyclopedia
• episode
• interview
• journal
• magazine
• mailing list
• map
• medrxiv
• news
• newsgroup
• podcast
• press release
• report
• serial
• sign
• speech
• ssrn
• tech report
• thesis
• web

Pages with this error are automatically placed in Category:CS1 errors: cite module (0 pages).<section end="module_cite_help_text" /><section begin="notes_help_text" />

Notes

Template:Reflist<section end="notes_help_text" /><section begin="references_help_text" />

References

Template:Reflist<section end="references_help_text" />