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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>
    <alltransclusions gatcontinue="Contrib|217" />
  </query-continue>
  <query>
    <pages>
      <page pageid="70" ns="6" title="File:Terminology for Flags.jpg" />
      <page pageid="72" ns="6" title="File:Terminology for Flags 2.jpg" />
      <page pageid="73" ns="6" title="File:Terminology for Flags 3.jpg" />
      <page pageid="74" ns="6" title="File:Terminology for Flags 4.jpg" />
      <page pageid="122" ns="6" title="File:Brunswick Grenadier Mitre Frontplate 1777.jpg" />
      <page pageid="123" ns="6" title="File:Brunswick Grenadier Mitre Frontplate 1750.jpg" />
      <page pageid="126" ns="6" title="File:Hesse-Kassel Grenadier Mitre Frontplate 1760.jpg" />
      <page pageid="153" ns="6" title="File:Browne Memorial Stone.jpg" />
      <page pageid="195" ns="6" title="File:De Ville Memorial Stone.jpg" />
      <page pageid="200" ns="6" title="File:Castle of Luzancy.jpg" />
    </pages>
  </query>
</api>