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HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <links plcontinue="1|0|Document_GPF_activities_by_Sandra_Villamizar" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page">
        <links>
          <pl ns="0" title="Document GPF activities" />
          <pl ns="0" title="Document GPF activities by Allen Pope" />
          <pl ns="0" title="Document GPF activities by Cedric David" />
          <pl ns="0" title="Document GPF activities by Heath Mills" />
          <pl ns="0" title="Document GPF activities by Ibrahim Demir" />
          <pl ns="0" title="Document GPF activities by Ji-Hyun Oh" />
          <pl ns="0" title="Document GPF activities by Jon Goodall" />
          <pl ns="0" title="Document GPF activities by Kyo Lee" />
          <pl ns="0" title="Document GPF activities by Leif Karlstrom" />
          <pl ns="0" title="Document GPF activities by Mimi Tzeng" />
        </links>
      </page>
    </pages>
  </query>
</api>