Help:CS1 errors: Difference between revisions

==Controlling error message display==

===Error and maintenance messages===

To display <span style="color:#3a3">maintenance messages</span>, include the following text in your common [[Cascading Stylesheets|CSS]] page or your specific skin's CSS page ([[Special:MyPage/common.css|common.css]] and [[Special:MyPage/skin.css|skin.css]] respectively):

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

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

<syntaxhighlight lang="css">.mw-parser-output span.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 [[WP:VPT|the technical village pump]] if you do not understand how.<section end="show_all_messages_help_text" /><section end="show_error_messages_help_text" />

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

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

::{{code|lang=css|.cs1-prop-jul-greg-uncertainty {}|}} – {{cl|CS1: Julian–Gregorian uncertainty}}

* [[#Cite &lt;template> requires %7C&lt;param>=]], ~57k pages

* [[#Citation without a title of any form]], ~36k pages

* [[#Cite uses generic name]], ~32k pages

* [[#Bare URL without a title]], ~25k pages

* [[#External link in %7C&lt;param>=]], ~19k pages

{{cs1}} templates {{tlx|cite web}}, {{tlx|cite news}}, {{tlx|cite journal}}, {{tlx|cite press release}}, {{tlx|cite podcast}}, {{tlx|cite newsgroup}}, as well as template {{tlx|citation}} when it uses {{para|work}} or any of its aliases, do not support {{para|chapter}} or the aliases {{para|contribution}}, {{para|entry}}, {{para|article}}, or {{para|section}}.

* use a more appropriate citation template, or

* [[zero-width joiner]], U+200D

If the {{para|asin}} value is correct and all-numeric, use {{para|isbn}} instead and delete any {{para|asin-tld}} parameters.  Articles with CS1 citations that use {{para|asin}} with all numeric values are categorized in {{cl|CS1 maint: ASIN uses ISBN}}.

<div class="plainlist">

When {{cs1}} and {{cs2}} templates contain date-holding parameters, an automated test is done to see if the dates are real dates that comply with a [[Help:Citation_Style_1#Date_compliance_with_Wikipedia's_Manual_of_Style|subset of the date rules]] in  Wikipedia's Manual of Style, specifically checking for violations of [[Wikipedia:Manual of Style/Dates and numbers#Dates and years|MOS:DATEFORMAT]].

* {{para|access-date}} must specify a day, not just a month or year.

* extraneous text  

To resolve this error, ensure that the {{para|isbn}} 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'.

<div class="plainlist">

==<span id="bad_message_id">Check |message-id= value</span>==

<section begin="bad_message_id_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_bad_usenet_id}}

The {{para|message-id}} parameter holds the unique identifier associated with a netnews message.<ref>{{cite web |url=//tools.ietf.org/html/rfc5536 |title=Netnews Article Format |website=[[Internet Engineering Task Force]] |at=[//tools.ietf.org/html/rfc5536#section-3.1.3 3.1.3] |rfc=5536 |date=November 2009}}</ref>  The value in {{para|message-id}} is checked to make sure that it contains <code>@</code> between left and right identifiers. {{para|message-id}} is also checked to make sure that the first character is not <code>&lt;</code> and the last character is not <code>></code>. [[Module:Citation/CS1]] adds the [[URI scheme]] <code>news:</code> to the value in {{para|message-id}}.  If the value in {{para|message-id}} is wrapped in <code><...></code> characters, the link created fails.

<div class="plainlist">

<section begin="bad_url_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_bad_url|$1=<code class="cs1-code">{{pipe}}url=</code>}}

External links in {{cs1}} and {{cs2}} templates are made from two parts: the ''title'' ({{para|title}}, {{para|chapter}}, etc.) and the ''URL'' ({{para|url}}, {{para|archive-url}}, {{para|chapter-url}}, {{para|lay-url}}, etc.). The {{para|url}} parameter and other URL parameters must begin with a supported [[URI scheme]]. The URI schemes <code>http://</code>, <code>https://</code> and the protocol relative scheme <code>//</code> are most commonly used; <code>irc://</code>, <code>ircs://</code>, <code>ftp://</code>, <code>news:</code>, <code>mailto:</code> and <code>gopher://</code> are also supported.

The URL field is checked to ensure that it contains only Latin characters and does not contain spaces.  The URL may be protocol relative (begins with <code>//</code>).  If there are no spaces and the URL is not protocol relative, then the scheme must comply with <nowiki>RFC 3986</nowiki>.<ref>{{citation |mode=cs1 |contribution-url=http://tools.ietf.org/html/std66#section-3.1 |contribution=Scheme |title=Uniform Resource Identifier (URI): Generic Syntax |publisher=[[Internet Engineering Task Force]] |date=January 2005 |rfc=3986}}</ref> 

{{#invoke:Cs1 documentation support|help_text_error_messages|err_bad_url|$1=<code class="cs1-code">{{pipe}}archive-url=</code>}}

 

The cs1|2 templates expect that {{para|archive-url}} will hold a unique URL for an archived snapshot of the source identified by {{para|url}} or {{para|chapter-url}} (or any of its aliases).  This error message is emitted when the value assigned to {{para|archive-url}} is the same as the matching title or chapter URL.   

To resolve this error, ensure that {{para|url}} and other URL parameters contain valid URLs.  Online tools are available to [[Internationalized domain name|internationalize]] URLs that are written in non-Latin scripts:

* {{cite web |url=https://www.verisign.com/en_US/channel-resources/domain-registry-products/idn/idn-conversion-tool/index.xhtml?loc=en_US |title=IDN Conversion Tool |website=Verisign }}

This error message is hidden.  To show this error message see [[Help:CS1 errors#Controlling error message display|Controlling error message display]].

This error message highlights CS1|2 templates that hold empty parameters with names that are not known to CS1|2.  This error message is a companion to [[Help:CS1 errors#parameter_ignored|Unknown parameter {{pipe}}xxxx= ignored]].

Empty positional parameters, which typically look like two adjacent pipes in a template, <code><nowiki>| |</nowiki></code>, or a pipe and then the end of the template, <code><nowiki>|}}</nowiki></code>, are identified as numbered parameters: {{error-small|{{para|1|plain=yes}}}}.  Similarly, a pipe followed by an HTML comment that encloses everything before the next pipe or closing brace, <code>| &lt;!--&lt;{{var|param name/value pair}}>--> |</code> 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: <code>|=</code> or <code>| =</code> → {{error-small|{{para|(empty string)|plain=yes}}}}.  Various templates that wrap CS1|2 templates may cause this error when they use constructs like this: <code><nowiki>|{{#if:{{{2|}}}|title}}={{{2|}}}</nowiki></code>.  When <code><nowiki>{{{2|}}}</nowiki></code> does not have a value, the template creates <code>|=</code>.

To resolve this error, remove the extra pipe, correct the parameter name, or remove the parameter from the CS1|2 template.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_param_unknown_empty|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="param_unknown_empty_help_text" />

In some cases, an incorrect template has been used (e.g. {{tlx|cite journal}} for a web page, book, or standalone document). The appropriate resolution in these cases is to change the incorrect template to {{tlx|cite web}}, {{tlx|cite book}}, or a different, more appropriate template.

| {{para|lay-date}}<!-- none deprecated at present -->|| rowspan="4" | if the source named by these parameters is important to the Wikipedia article, create a cs1|2 template for that source with all of the appropriate bibliographic information<!-- --> || rowspan="4" |2021-01-03

| {{para|transcripturl}} || {{para|transcript-url}} || 2022-01-22

! style="width: 12em;" | Removed parameter !! Replace with !! style="width: 6em;" | Date

| {{para|authorfirst}}

| {{para|author-first}}

| {{para|authorfirst{{var|n}}}}

| {{para|author-first{{var|n}}}}

| {{para|author{{var|n}}first}}

| {{para|author{{var|n}}-first}}

| {{para|authorgiven}}

| {{para|author-given}}

| {{para|authorgiven{{var|n}}}}

| {{para|author-given{{var|n}}}}

| {{para|author-mask}}

|-

| {{para|authormask{{var|n}}}}

| {{para|author-mask{{var|n}}}}

|-

| {{para|author{{var|n}}mask}}

| {{para|author{{var|n}}-mask}}

| {{para|authorsurname{{var|n}}}}

| {{para|author-surname{{var|n}}}}

| {{para|conferenceurl}}

| {{para|conference-url}}

|-

| {{para|contributionurl}}

| {{para|deadurl|yes}}<!-- deprecation already some while ago, but gets reinserted into mainspace by old scripts, so continue to list until resolved -->

| {{para|dead-url|yes}}<!-- deprecation already some while ago, but gets reinserted into mainspace by old scripts, so continue to list until resolved -->

| {{para|url-status|dead}}

| {{para|displayauthors}}

| {{para|display-authors}}

| {{para|displayeditors}}

| {{para|display-editors}}

|-

| <s>May 2021</s>

|}<section end="deleted_params_table" />

==<span id="generic_name">Cite uses generic name</span>==

<section begin="generic_name_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_generic_name|$1=&lt;param>}}

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.

{{Notice|1=This feature is new and currently has several fixes pending.  If your concern has not been reported, please report it at [[Help talk:Citation Style 1/Archive 81#Generic names change]].}}  

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

{{div col begin |colwidth=15em}}

*<code>about us</code>

*<code>author</code>

*<code>contributor</code>

*<code>contact us</code>

*<code>home page</code>

*<code>instagram</code>

*<code>linkedIn</code>

*<code>pinterest</code>

*<code>policy</code>

*<code>translator</code>

*<code>tumblr</code>

{{div col end}}

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.  

* Replace {{para|author|Smith, Jane, editor}} with {{para|editor|Smith, Jane}}

* Replace <code><nowiki>|author=[[Jane Smith (author)|Jane Smith]]</nowiki></code> with <code><nowiki>|author=Jane Smith |author-link=Jane Smith (author)</nowiki></code>

False positives are possible. When the name is valid, wrap the parameter value in the [[Help:Citation_Style_1#Accept-this-as-written_markup|accept-this-as-written markup]]:

:{{para|author|((Super User))}}

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

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_generic_name|pages=yes}}.<ref group="lower-alpha" name="categories" />

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

Articles are listed in this category when [[Module:Citation/CS1]] identifies template {{para|title}} 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:

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.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_generic_title|pages=yes}}.<ref group="lower-alpha" name="categories" />

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" />

==<span id="citeseerx_missing">|citeseerx= required</span>==

<section begin="citeseerx_missing_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_citeseerx_missing}}

{{tlx|cite citeseerx}} requires the identifier parameter {{para|citeseerx}}.

To resolve this error, ensure that the template has {{para|citeseerx}} with a properly constructed value.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_citeseerx_missing|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="citeseerx_missing_help_text" />

==<span id="class_ignored">|class= ignored</span>==

<section begin="class_ignored_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_class_ignored}}

Only used in {{tlx|cite arXiv}} templates, {{para|class}} is only appropriate when the template uses {{para|arxiv|YYMM.NNNN}} or {{para|arxiv|YYMM.NNNNN}} identifier formats; see [[Template:Cite arXiv#Usage|Cite arXiv §Usage]].

To resolve this error, remove {{para|class}}.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_class_ignored|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="class_ignored_help_text" />

<section begin="contributor_ignored_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_contributor_ignored}}

Only used in book citations, {{para|contributor}} identifies the author of a contribution, typically an afterword, foreword, introduction, preface, etc., to another (primary) author's work.  This error occurs when {{para|contributor}} is used in a template that is not {{tlx|cite book}} or {{tlx|citation}} or is one of these two templates and one of the {{para|work}} parameter aliases is set.

To resolve this error, consider the {{para|others}} parameter, choose a more appropriate CS1 or CS2 template or remove {{para|contributor}}.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_contributor_ignored|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="contributor_ignored_help_text" />

 

==<span id="contributor_missing_required_param">|contributor= requires |&lt;param>= </span>==

<section begin="contributor_missing_required_param_help_text" />{{help desk}}{{plainlist|

*{{#invoke:Cs1 documentation support|help_text_error_messages|err_contributor_missing_required_param|$1=author}}

*{{#invoke:Cs1 documentation support|help_text_error_messages|err_contributor_missing_required_param|$1=contribution}}}}

 

Only used in book citations, {{para|contributor}} 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 ({{para|author}} or appropriate alias) as is the title of the contribution ({{para|contribution}}). 

 

To resolve this error, include the book's primary author in {{para|author1}}, or {{para|last1}}, {{para|first1}}, or {{para|vauthors}} and include the contribution title in {{para|contribution}}; or consider the {{para|others}} parameter or remove {{para|contributor}}.

 

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_contributor_missing_required_param|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="contributor_missing_required_param_help_text" />

==<span id="doibroken_missing_doi">|doi-broken-date= requires |doi=</span>==

When {{para|doi-broken-date}} is used in a CS1|2 template, {{para|doi}} (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 {{#invoke:cs1 documentation support|help_text_cats|err_doibroken_missing_doi|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="doibroken_missing_doi_help_text" />

==<span id="extra_text_edition">|edition= has extra text </span>==

<section begin="extra_text_edition_help_text" />{{help desk}}

{{#invoke:Cs1 documentation support|help_text_error_messages|err_extra_text_edition}}

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

:{{para|edition|1st}}

The templates emit this error message when various forms of <code>ed</code>, <code>edn</code>, or <code>edition</code> are found in the value assigned to {{para|edition}}.

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

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_extra_text_edition|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="extra_text_edition_help_text" />

<section begin="empty_citation_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_empty_citation}}

A {{cs1}} or {{cs2}} template marked as "Empty" contains no recognizable parameter identifiers. For example, this citation is marked as "empty" even though it contains usable information:

:<code><nowiki>{{cite web |http://www.foobar.com |The Foobar News}}</nowiki></code>

The citation is "empty" because it does not contain the necessary parameter identifiers (in this case {{para|url}} and {{para|title}}) that tell {{tlx|cite web}} how to use the information that the citation does contain.

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

: <code><nowiki>{{cite book |titolo=The Bazquux Uprising |anno=2015}}</nowiki></code>

This citation is "empty" because the Italian-language parameters {{para|titolo}} and {{para|anno}} 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 {{tlx|citation}} when the intent was to use {{tlx|citation needed}} or {{tlx|quote}}.

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 {{#invoke:cs1 documentation support|help_text_cats|err_empty_citation|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="empty_citation_help_text" />

== <span id="explicit_et_al">Explicit use of et al.</span> ==

<section begin="explicit_etal_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_etal|$1=&lt;param>}}

This error occurs where a {{cs1}} or {{cs2}} template detects that one of the names parameters contains some form of "et al." either as a separate name parameter ({{para|author6|et al.}}) or as a suffix added to a name list ({{para|author|Smith, A.B. et al.}}) or first name ({{para|first|John, et al.}}).

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

Use the {{para|display-authors}} parameter instead (or other applicable {{para|display-''<names>''}} parameter), as documented at [[Help:Citation Style 1#Display options]].

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_etal|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="explicit_etal_help_text" />

==<span id="param_has_ext_link">External link in |&lt;param>=</span>==

<section begin="param_has_ext_link_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_param_has_ext_link|$1={{pipe}}&lt;param>=}}

 

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

{{div col begin}}

*{{para|archive-url}}

*{{para|article-url}}

*{{para|chapter-url}}

*{{para|conference-url}}

*{{para|contribution-url}}

*{{para|entry-url}}

*{{para|{{xtd|lay-url}}}} – deprecated

*{{para|map-url}}

*{{para|section-url}}

*{{para|transcript-url}}

*{{para|url}}

*{{para|page}}

*{{para|p}}

*{{para|pages}}

*{{para|pp}}

*{{para|at}}

*{{para|quote-page}}

*{{para|quote-pages}}

* for {{para|chapter}}, the URL may belong in {{para|chapter-url}}.

* for other parameters, it may belong in {{para|url}}.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_param_has_ext_link|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="param_has_ext_link_help_text" />

==<span id="first_missing_last">|&lt;first>''n''= missing |&lt;last>''n''=</span>==

<section begin="first_missing_last_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_first_missing_last|$1=&lt;first>{{var|n}}|$2=&lt;last>{{var|n}}}}

{{cs1}} and {{cs2}} templates requires a {{para|&lt;last>''n''}} parameter for each {{para|&lt;first>''n''}} 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 {{para|&lt;last>''n''}} have a matching {{para|&lt;first>''n''}}.

To resolve this error, ensure that each {{para|&lt;first>''n''}} has a corresponding {{para|&lt;last>''n''}}.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_first_missing_last|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="first_missing_last_help_text" />

==<span id="format_missing_url">|format= requires |url= </span>==

<section begin="format_missing_url_help_text" />{{help desk}}{{plainlist|

*{{#invoke:Cs1 documentation support|help_text_error_messages|err_format_missing_url|$1=format|$2=url}}

*{{#invoke:Cs1 documentation support|help_text_error_messages|err_format_missing_url|$1=...-format|$2=...-url}}}}

These errors occur when {{cs1}} and {{cs2}} templates use {{para|format}} or {{para|...-format}} without also providing a corresponding URL for {{para|url}} or {{para|...-url}}, respectively. The {{para|format}} and {{para|...-format}} parameters are used to specify the file format of a web resource, such as [[PDF]], [[Doc (computing)|DOC]], or [[Microsoft Excel file format|XLS]]. In some cases an editor may have intended to use {{para|type}} to specify a kind of document, such as hard cover, paperback, or pamphlet. The {{para|format}} and {{para|...-format}} value is always displayed.

The list of {{para|...-format}} parameters is:

: {{para|archive-format}}, {{para|article-format}}, {{para|chapter-format}}, {{para|conference-format}}, {{para|contribution-format}}, {{para|entry-format}}, {{para|event-format}}, {{para|lay-format}}, {{para|map-format}}, {{para|section-format}}, {{para|transcript-format}}

(<!-- TBD: Ia this still necessary to be mentioned? -->Citations that relied on the pre-2014<!-- 2014-11-29 -->, somewhat odd use of {{para|url}} and {{para|format}} may need adjustment in regard to {{para|chapter-format}}.)

To resolve this error, remove {{para|format}} or {{para|chapter-format}}; define {{para|url}} or {{para|chapter-url}}; or change {{para|format}} to {{para|type}} (or to {{para|chapter-format}} if {{para|chapter-url}} is used without {{para|url}}.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_format_missing_url|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="format_missing_url_help_text" />

==<span id="disp_name">Invalid |display-&lt;names>=&lt;value></span>==

<section begin="disp_name_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_disp_name|$1=&lt;names>|$2=&lt;value>}}

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

* Remove the {{para|display-&lt;names>}} parameter from the citation (because "et al." is not appropriate in the citation)

* Change the <code>&lt;value></code> of the {{para|display-&lt;names>}} parameter such that it is less than the number of <code>&lt;names></code> in the name-list (thereby truncating the displayed list to the number)

* Change the <code>&lt;value></code> of the {{para|display-&lt;names>}} parameter to <code>etal</code>, which will cause "et al" to display after the last <code>&lt;name></code>.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_disp_name|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="disp_name_help_text" />

==<span id="invalid_param_val">Invalid &lt;param>=&lt;value></span>==

<section begin="invalid_param_val_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_invalid_param_val|$1=&lt;param>|$2=&lt;value>}}

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.