Extension:Cite/Cite.php

Cite.php is a Cite extension that adds two parser hooks to MediaWiki, <ref> and <references />; these operate together to add citations to pages.

Usage

The basic concept of the <ref> tag is that it inserts the text enclosed by the ref tags as a footnote in a designated section, which you indicate with the placeholder tag <references />. This format cannot be used interchangeably with the older format — you must pick one or the other.

If you forget to include <references /> in the article, the footnotes will not appear, but a red error message will be displayed at the end of the page.

This page itself uses footnotes, such as the one at the end of this sentence. If you view the source of this page by clicking "Edit this page", you can see a working example of footnotes.

Example

According to scientists, the Sun is pretty big.<ref>E. Miller, The Sun, (New York: Academic Press, 2005), 23-5.</ref>
The Moon, however, is not so big.<ref>R. Smith, "Size of the Moon", Scientific American, 46 (April 1978): 44-6.</ref>

==Notes==
<references />

Multiple uses of the same footnote

To give a footnote a unique identifier, use <ref name="name">. You can then refer to the same footnote again by using a ref tag with the same name. The text inside the second tag doesn't matter, because the text already exists in the first reference. You can either copy the whole footnote, or you can use a terminated empty ref tag that looks like this: <ref name="name" />. The quotes are not required (but not incorrect) if the name contains no embedded spaces. The space before the closing "/" may be omitted.

In the following example, the same source is cited three times.

This is an example of multiple references to the same footnote.<ref name="multiple">Remember that when you refer to the same footnote multiple times, the text from the first reference is used.</ref>

Such references are particularly useful when citing sources, if different statements come from the same source.<ref name="multiple">This text is superfluous, and won't show up anywhere. We may as well just use an empty tag.</ref>

A concise way to make multiple references is to use empty ref tags, which have a slash at the end. Although this may reduce redundant work, please be aware that if a future editor removes the first reference, this will result in the loss of all references using the empty ref tags.<ref name="multiple" />

==Notes==
<references />

The text above gives the following result in the article (see also section below):

This is an example of multiple references to the same footnote.

Such references are particularly useful when citing sources, when different statements come from the same source.

A concise way to make multiple references is to use empty ref tags, which have a slash at the end. Although this may reduce redundant work, please be aware that if a future editor removes the first reference, this will result in the loss of all references using the empty ref tags.

Note: name= identifiers require alphabetic characters; solely relying on numerals will generate an error message

Merging two texts into a single reference (wikisource issue)

A typical wikisource issue is, how to merge into one reference texts split into different pages. This can be done using a <ref name="name"> tag for the first part of the reference, and tagging the following parts into different pages with a tag <ref follow="name">.

Here an example, deriving the text used into previous section:

This is an example of merging multiple texts into the same footnote.<ref name="main">Remember that all the texts will be
included into the reference containing the ''name='' attribute.<br /></ref>

<ref follow="main">Simply include the text to be merged into the first <ref name="name"> reference with a tag <ref follow="name"><br />This paragraph is included into a similar tag and it will be merged into the reference in former paragraph. </ref>

Result: This is an example of merging multiple texts into the same footnote.

When using this syntax into Page: namespace, take care that the ref follow part of the footnote is transcluded too into the same ns0 page, where the first part of footnote is transcluded. Use appropriately section tags to get this result. To also remind users that reference names should not solely be numbers, eg. <ref name="p32"> and <ref follow="p32">.

<references />

Placing <references /> inserts the full text of all pending inline citations defined by <ref>, anywhere on the page. For example, based on the citations above, the code:

<references />

will yield:

In some language editions of Wikipedia, long reference lists may be placed using the template {{Reflist}}, which incorporates <references />. It provides an optional parameter to display the reference list in multiple columns. For instance, the English, Hindi and Interlingua Wikipedias use the css selector references-small to make the reference text smaller than normal text.

In the case of multiple references-tags on a page, each gives the references defined in the ref-tags from the previous references-tag. In the case that these references-tags are produced by templates, each gives the references defined in the ref-tags before the first references-tag, and there is an error message that there is a ref-tag but not a references-tag.

List-defined references

Instead of using a self-closing <references /> (void element) to display pending inline citations, one can use paired tags – <references>...</references> – containing named references, as in:

<references>
<ref name=foo>...</ref>
<ref name=bar>...</ref>
</references>

These can then be referenced via <ref name=foo /> tags, and allow one to define references at the end, instead of inline. Pending inline references will also be displayed. See Help:List-defined references for an example of this use.

Grouped references

The following example generates separate reference lists for citations and miscellaneous footnotes:

According to scientists, the Sun is pretty big <ref>E. Miller, The Sun, (New York: Academic Press, 2005), 23-5.</ref>.
In fact, it is very big <ref group="footnotes">Take their word for it. Don't look directly at the sun!</ref>.

==Notes==
<references group="footnotes" />
==References==
<references />

The anonymous group works as before, while the named group reference will show up as , and the references will look like this:

Separating references from text

In-text references make it easy to copy the text to another page; on the other hand, they make it hard to read. References containing a lot of data, quotes or elaborate citation templates can make up a significantly larger fraction of the source than the text that will actually be visible. To avoid this, recent versions of the extension allow moving some or all of the references into the <references /> section, to the place where they will actually appear to the reader. Thus,

According to scientists, the Sun is pretty big.<ref name="miller" />
The Moon, however, is not so big.<ref name="smith" />

==Notes==
<references>
<ref name="miller">E. Miller, The Sun, (New York: Academic Press, 2005), 23-5.</ref>
<ref name="smith">R. Smith, "Size of the Moon", Scientific American, 46 (April 1978): 44-6.</ref>
</references>

will have the same output as the first example above, although the numbering and order of the references will not in general be the same.

Substitution and embedded parser functions

Since <ref> is parsed before substitution (i.e., subst:) or parser functions (i.e., {{#if:}}), they will not work inside of citation references. Instead, you have to use the #tag magic word.

This non-working example

<ref name="Resource">Content that can include subst: and parser functions (like {{#if:}} and {{PAGENAME}})</ref>

could be made to work using

{{#tag:ref|Content that can include subst: and parser functions (like {{#if:}} and {{PAGENAME}})|name="resource"}}

At this time, there is no way to create an "empty" tag (i.e., <ref name="resource" />) without triggering Cite's complaint about empty content. The workaround is to simply redefine the full tag each time you use this feature. Since such usage is likely limited to templates or other semi-automated process, this may not be too onerous.

Customization

The format of the output of <ref> and <references> is almost completely customizable through MediaWiki messages, that can be modified, for example, through the MediaWiki namespace depending on the configuration of the wiki.

For a list of messages that control the output of <ref> and <references> and the values, if any, that are passed to them ($1, $2, $3 ...), see the code in CVS for an up-to-date listing of their default contents.

• cite_reference_link_key_with_num
  1. key
  2. num
• cite_reference_link_prefix
• cite_reference_link_suffix
• cite_references_link_prefix
• cite_references_link_suffix
• cite_reference_link
  1. ref ID
  2. backlink ID
  3. count to display
• cite_references_link_one
  • Used to format the source list that <references /> outputs, it configures 3 things: the backlink ID, the ref ID, and text of note.
  1. backlink ID - used for creating the number order of the source list.
  2. ref ID - used to link back to the actual reference in the text, this is where you can configure the <bold>^</bold> symbol
  3. text of note - text used above describing the source info
• cite_references_link_many
  1. backlink ID
  2. list of links
  3. text of note
• cite_references_link_many_format
  1. ref ID
  2. numeric value to use as a backlink
  3. custom value (as defined in cite_references_link_many_format_backlink_labels to use as a backlink)
• cite_references_link_many_format_backlink_labels
• cite_references_link_many_sep
• cite_references_link_many_and
• cite_references_prefix
• cite_references_suffix

Set references to use ^ and letters like Wikipedia

Modify the following system messages. All of these pages can be found on Special:Allmessages:

On the page MediaWiki:Cite references link one change:

<li id="$1">[[#$2|↑]] $3</li>

to

<li id="$1">[[#$2|^]] $3</li>

On the page MediaWiki:Cite references link many change:

<li id="$1">↑ $2 $3</li>

to

<li id="$1">^ $2 $3</li>

On the page MediaWiki:Cite references link many format change:

[[#$1|^$2]]

to:

[[#$1|^$3]]

Explanation:

The ^ replaces the up arrows.

Putting $3 between the  tags changes the links from 1.0, 1.1, 1.2 to a, b, c etc...

Searching for these 3 pages for the first time will result in no matches. Simply click "Create this page" to edit the code. The changes will not show up until a page with references is rebuilt.

Set reference and reference number highlighting like Wikipedia

Add the following code to the MediaWiki:Common.css page.

/* make the Cite extension list of references look smaller and highlight clicked reference in blue */
ol.references { font-size: 90%; }
ol.references li:target { background-color: #ddeeff; }
sup.reference:target { background-color: #ddeeff; }

Source: Wikipedia's MediaWiki:Common.css