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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>
    <allpages gapcontinue="Retiree" />
  </query-continue>
  <query>
    <pages>
      <page pageid="134" ns="0" title="Rencontres de Moriond on Electroweak Interactions and Unified Theories 2013">
        <revisions>
          <rev xml:space="preserve">{{Conference
|NAME=Rencontres de Moriond on Electroweak Interactions and Unified Theories 2013
|VENUE=Planible Hotel
|LOCATION=La Thuile, Italy
|START DATE=2013/03/02
|END DATE=2013/03/09
|REGISTRATION DATE=2013/01/31
|URL=http://moriond.in2p3.fr
|DOE CONFERENCE=No
}}</rev>
        </revisions>
      </page>
      <page pageid="140" ns="0" title="Rencontres de Moriond on QCD and High Energy Interactions 2013">
        <revisions>
          <rev xml:space="preserve">{{Conference
|NAME=Rencontres de Moriond on QCD and High Energy Interactions 2013
|VENUE=Planible Hotel
|LOCATION=La Thuile, Italy
|START DATE=2013/03/09
|END DATE=2013/03/16
|REGISTRATION DATE=2013/01/31
|URL=http://moriond.in2p3.fr/J13
|DOE CONFERENCE=No
|MEETING TYPE=Conference
}}</rev>
        </revisions>
      </page>
    </pages>
  </query>
</api>