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Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
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<?xml version="1.0"?>
<api>
  <query>
    <pages>
      <page pageid="223" ns="0" title="WikiCredits">
        <revisions>
          <rev contentformat="text/x-wiki" contentmodel="wikitext" xml:space="preserve">== Anope IRC Services Wiki Credits ==

The following is the list of members who have contributed to the development or content of the Wiki. You can click a users name to view a list of their contributions.

* [http://wiki.anope.org/index.php/Special:Contributions/Dukepyrolator DukePyrolator]  -- Anope Project Leader
* [http://wiki.anope.org/index.php/Special:Contributions/Mietzie Mietzie] -- Anope Contributor (Wiki)
* [http://wiki.anope.org/index.php/Special:Contributions/Yoerger Yoerger] -- Anope Contributor (Support, Wiki Admin)
* [http://wiki.anope.org/index.php/Special:Contributions/Azander Azander] -- Anope Contributor (Wiki)</rev>
        </revisions>
      </page>
    </pages>
  </query>
</api>