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Specify the format parameter to change the output format.
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<?xml version="1.0"?>
<api>
  <query>
    <pages>
      <page ns="0" title="API" missing="" />
      <page pageid="1" ns="0" title="Main Page">
        <revisions>
          <rev user="Chefkoch" timestamp="2013-12-25T17:25:58Z" comment="Protected &quot;[[Main Page]]&quot; [edit=sysop:move=sysop]" contentformat="text/x-wiki" contentmodel="wikitext" xml:space="preserve">'''Vendetta Lua Interface Documentation Wiki'''

This is a friendly introduction.

[[Overview]]

[[API Index2|API Index]] ([[API Index|Large version]])

[[API Changes]]

[[Requests]]

[[Eventtype|List of Events]]

[[Plugins]]

[[DragDrop|Drag and Drop functionality]]

[[ThreadApi|Thread API]]

[[TouchControls |Understanding Touch Controls]]

[[Links]]</rev>
        </revisions>
      </page>
    </pages>
  </query>
</api>