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HTML is good for debugging, but is unsuitable for application use.
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To see the non HTML representation of the XML format, set format=xml.
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<?xml version="1.0"?>
<api>
  <query-continue>
    <alltransclusions gatcontinue="Option_Detection|1569" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1563" ns="0" title="APP/APG v2.0 Correction de la géométrie" />
      <page pageid="1567" ns="0" title="APP/APG v2.0 Options de rendu" />
      <page pageid="1745" ns="0" title="Interpolateur et mélangeur" />
      <page pageid="1997" ns="10" title="Modèle:Lien sur image" />
      <page pageid="1998" ns="10" title="Modèle:Clic" />
      <page pageid="2163" ns="0" title="V1.4 - Correction de la géométrie" />
      <page pageid="2260" ns="0" title="V1.4 - Comprendre les types de projection" />
    </pages>
  </query>
</api>