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Shortcut H:CERMK

This page will help you to fix the cite error message:

A list-defined reference named "$1" is not used in the content (see the help page).

• If you have read this help page and find something missing or confusing, please discuss it at the main talk page.
• Please reference this page and the page where you have the problem so we can understand your issues.
• For basic information on the footnotes system, see Referencing for beginners; for advanced help, see Footnotes.

A footnote used multiple times may be defined with a name:

<ref name="foo">content</ref>

To invoke a named footnote:

<ref name="foo" />

References may also be defined within the reference list:

((reflist|refs=
<ref name=rename1>refcontent1</ref>
<ref name=rename2>refcontent2</ref>
<ref name=rename3>refcontent3</ref>
<ref name=rename4>refcontent4</ref>
))

List-defined references may be invoked by the standard markup or by use of ((r)).

All references defined in the reference list must be invoked in the content. Unused references must be removed or commented out.

Including more than one nested reference in List-defined references will cause a Cite error.

Misusing a template that was never intended as a citation template and placing it in <ref> tags may cause this issue.

A template that creates <ref> tags; known instances:

• ((Certification Cite Ref))
• ((sfn)) and variants
• ((Single chart))

A template that includes table markup; known instances:

• ((Certification Table Entry))

The content of this message is dependent on the language setting in Special:Preferences. You can test how the error messages look in the most popular languages with these links: বাংলা English español British English français português do Brasil русский Deutsch Bahasa Indonesia العربية 中文（中国大陆） română italiano Türkçe

Ex. 1) There are three references defined in the list, but none are invoked in the content. Note the spurious error for the first reference named ipsum:

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.

==References==
((reflist|refs=
<ref name=ipsum>Reference1</ref>
<ref name=minim>Reference2</ref>
<ref name=dolor>Reference3</ref>
))

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.

Ex. 2) If only one reference is defined but not invoked, then only the spurious error is shown:

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.

==References==
((reflist|refs=
<ref name=ipsum>Reference1</ref>
))

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.

Ex. 3) Not so obvious case. If you mistakenly nest an ((sfn)) type template inside <ref></ref> as in the second footnote below, an error message will show:

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.<ref>((harvp|foo|1999|p=123))</ref> Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.<ref>((sfnp|Foo|1999|p=123))</ref>

==References==
((reflist))
*((citation|last=foo|title=foobar|year=1999))

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.^[1] Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.^[2]

• Foo (1999), Foobar

Pages with this error message are placed into Pages with incorrect ref formatting. The system message page is at Cite error references missing key.

• T24635 Multiple problems with refs inside <references>...</references> blocks.
• T26600 The first defined reference that is not invoked will show an incorrect error message.
• T22707 Nested refs fail inside references block