 | This page is a how-to guide detailing a practice or process on the English Wikipedia. |
The Wikipedia footnotes system has the ability to detect errors. This page documents the error messages and provides an understanding of the problem and solutions.
[edit] Overview
Cite.php is the software extension for the footnotes system. Two HTML-style tags are used to define and show the references.
<ref>
Single use footnotes are defined by enclosing content within <ref></ref>:
<ref>content</ref>
A footnote used multiple times may be defined with a name:
<ref name="foo">content</ref>
To invoke a named footnote:
<ref name="foo"/>
Footnotes may be defined in groups:
<ref group="foo">content</ref>
<references/>
To display the reference list, after all of the <ref></ref> tags, include:
<references/>
To display a list of references defined in a group, include:
<references group="foo"/>
Names for footnotes and groups are case sensitive. They may not be a numeric integer. The quotes are optional unless the name or group includes non-ASCII characters or a space, punctuation or other mark. Quote enclosed names may not include a less-than sign (<) or a quote symbol (").
It is recommended that names and groups be kept simple and restricted to the standard English alphabet and numerals.
[edit] Templates
Several templates have been developed for use with references:
- {{Reflist}} adds the
<references/> tag with some formatting options - {{R}} invokes up to five named references
- {{Sfn}} invokes named references for shortened footnotes
[edit] Error messages
The messages will be formatted as an error.
These messages are dependent on the language setting in Special:Preferences— this list applies only to "en — English."
Cite error: Invalid <ref> tag; refs with no name must have content. |
| Problem | There is no content between the <ref></ref> tags. |
| Solution | Either put content between the <ref> tags, for example:<ref>content</ref>; or, if you're reusing a named reference that's been defined elsewhere in the article use a single tag. <ref name="ref_name"/>
|
| Category | Category:Pages with incorrect ref formatting |
| MediaWiki | Cite error ref no input |
Cite error: Invalid <ref> tag; name cannot be a simple integer. Use a descriptive title. |
| Problem | The name of the reference is a pure number. To avoid naming conflicts— as unnamed references are automatically assigned numbers as names— this is not allowed. |
| Solution | Rename the reference to contain at least one letter (eg <ref name="foo"/> instead of <ref name="123"/>). It's good practice to give references meaningful names anyway. Ensure that when changing the name you update all the tags that refer to that reference! |
| Category | Category:Pages with incorrect ref formatting |
| MediaWiki | Cite error ref numeric key |
Cite error: Closing </ref> missing for <ref> tag. |
| Problem | A reference is missing the closing </ref>. |
| Solution | Make sure that you are either using a closed pair of tags (<ref>content</ref>), or one single tag with a forward slash at the end to mark it as a single tag (<ref/>). The last reference on a page will not show this error and will eat the following content. |
| Category | Category:Pages with incorrect ref formatting |
| MediaWiki | Cite error included ref |
Cite error: Invalid <ref> tag; no text was provided for refs named $1; see Help:Cite error. |
| Problem | A single ref tag named "foo" (<ref name="foo"/>) was invoked, but there is no full reference named "foo" (<ref name="foo">content</ref>) from which to get the reference text. The reference may be defined inline or in the reference list. |
| Solution | You may have misspelled the reference name, or used special characters that look the same but are actually different. For instance, <ref name="foo-bar">content</ref> and <ref name="foo–bar"/> are not the same: one contains a hyphen while the other uses an ndash. To avoid this sort of error, try to stick to the characters available on the standard keyboard. Alternatively, the full reference may have been removed from the article with other content, such as when removing information under BLP concerns. In this case the text of the reference will be available in the page history, and you can convert the single <ref/> tag into a full reference. |
| Category | Category:Pages with incorrect ref formatting |
| MediaWiki | Cite error references no text |
Cite error: There are <ref> tags on this page, but the references will not show without a <references/> tag. |
| Problem | - The
<references/> tag was not included at the end of the article. - The
<ref> tag immediately before <references/> does not have a closing </ref>. - There are
<ref></ref> tags after <references/> - There are multiple
<references/> tags in the article with <ref></ref> tags after the first. |
| Solution | - Add the {{reflist}} template at the bottom of the article in the "references" section; create one if it not already present, between "see also" and "external links"
- Fix the
<ref> tag as explained above - Move the
<references/> tag or the {{reflist}} template to below the last reference - There may be only one
<references/> tag and it should be after the body, unless a group is defined |
| Category | Category:Pages with incorrect ref formatting |
| MediaWiki | Cite error refs without references |
| Cite error: Ran out of custom backlink labels. Define more in the [[MediaWiki:Cite references link many format backlink labels]] message |
| Problem | A named reference was used more than 702 times, thereby exhausting the list of available labels ("a", "b"... "aa", "ab"... "zy", "zz"). |
| Solution | It should never be necessary to cite one source this many times. Consider the use of {{scref}} and {{scnote}} or a similar solution for a reference used a large number of times. |
| Category | Category:Pages with incorrect ref formatting |
| MediaWiki | Cite error references no backlink label |
Cite error: There are <ref> tags on this page, but the references will not show without a <references group="$1"/> tag. |
| Problem | - The group parameter was used in a reference, but the corresponding
<references/> tag was not included with a group parameter. - The reference immediately before
<references/> does not have a closing </ref>. - There are
<ref></ref> tags using a group after <references/>. |
| Solution | - Use the {{reflist}} template, setting
|group=GroupName ({{reflist|group=GroupName}}). - Fix as for normal
<references/> tags as explained above. |
| Category | Category:Pages with missing references list |
| MediaWiki | Cite error group refs without references |
| $1 |
| Problem | None; this message is used as a prefix for other messages and is currently blank.
|
| MediaWiki | Cite error |
[edit] Other problems
Some problems may not show a cite error message, while others may not be obvious.
[edit] Reference links show in the body of the article, but do not show in the reference list
This may be caused by a template that is not properly closed with }}.
It can also be caused by multiple footnotes that are defined to use the same name. Links will be generated for both, but only the first will show in the references list: For example:
<ref name="foo">content1</ref><ref name="foo">content2</ref>
Only content1 will show. refTools will catch this problem.
[edit] Content on a non-article page is missing
If a footnote does not have a closing </ref>, it will "eat" the following text, causing it to not show. This normally shows a cite error, unless it is the last footnote on the page. Normally, this would then suppress the <references/> tag, generating an error, but the message for a missing <references/> tag is suppressed on non-article pages. refTools will catch this problem.
[edit] Templates
Some templates may include <ref></ref> tags; for example {{botanist}}. If a template of this type in included without the <references/> tag, then an error is generated, but the problem is not obvious. refTools will not catch this problem.
Several methods are available for solving this problem. Below they are listed in order of preference. Note that only one of these is required, not all of them.
- Method 1
If the template has a documentation page, add <references/> there.
- Method 2
Add the following code to the end of the template:
<noinclude> {{Templaterefsection}} </noinclude> - Method 3
Add the following code to the end of the template:
<noinclude> <div style="display: none"><references /></div> </noinclude>
Cons: Hides the references, not informing the user that it is there; editors won't be able to check the references formatting.
- Method 4
Include the <references/> tag within the template itself using the group parameter. See Help talk:Cite errors/Testcases1 for an example.
Cons: Creates a separate references section that may not be obvious; does not allow reuse of the references within the body of the article.
refTools can be enabled via Preferences → Gadgets → refTools. It includes an error checking tool for common problems.
[edit] Messages, namespaces and categories
Internal messages are generated by the Cite.php extension and shown as a MediaWiki message. See the parser hooks section of Special:Version for the installed version of Cite.php. These messages are in the MediaWiki namespace and can be modified only by admins.
The MediaWiki messages use {{broken ref}} to control the namespace and category. Messages show only on main (article), user, template, category, help and file pages. Talk pages do not show error messages.
Category default sorting is by {{PAGENAME}} for the main namespace and by τ{{PAGENAME}} for template, category, help and file namespaces.
[edit] See also
