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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.
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<?xml version="1.0"?>
<api>
  <query-continue>
    <alltransclusions gatcontinue="Contrib|73" />
  </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="2885" ns="0" title="Bavarian Leib-Regiment" />
      <page pageid="2889" ns="0" title="Kurprinz Infantry" />
      <page pageid="2891" ns="0" title="Herzog Clemenz Infantry" />
      <page pageid="2893" ns="0" title="Minucci Infantry" />
      <page pageid="2896" ns="0" title="Morawitzky Infantry" />
      <page pageid="2898" ns="0" title="Preysing Infantry" />
      <page pageid="2900" ns="0" title="Holnstein Infantry" />
      <page pageid="2902" ns="0" title="Pechmann Infantry" />
    </pages>
  </query>
</api>