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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>
    <allfileusages gafcontinue="BKV_Position_Buckel_4.JPG|88" />
  </query-continue>
  <query>
    <pages>
      <page pageid="88" ns="0" title="Umbau auf Scheibenbremsen Volvo 444 / 544" />
      <page pageid="538" ns="0" title="Restauration Volvo 142" />
      <page pageid="1548" ns="0" title="Motorraum .Von Buckel bis 164.Optisches Tuning" />
      <page pageid="2743" ns="2" title="Benutzer:Robby Ross1" />
      <page pageid="6377" ns="0" title="Kalender 2013" />
    </pages>
  </query>
</api>