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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>
    <allfileusages gafcontinue="Belief_System1.jpg|34027" />
  </query-continue>
  <query>
    <pages>
      <page pageid="33604" ns="0" title="Animals and Awaretheory" />
      <page pageid="33605" ns="0" title="Science Fiction and Awaretheory" />
      <page pageid="33691" ns="0" title="Assemble Line Argument" />
      <page pageid="34027" ns="0" title="Belief System Tolerance and Awaretheory" />
      <page pageid="34225" ns="0" title="Conscious Enhancement and Awaretheory" />
      <page pageid="34273" ns="0" title="Matter is magical argument" />
      <page pageid="34486" ns="0" title="Simultaneous Multiplicity of Ixperiencitness" />
      <page pageid="34505" ns="0" title="Experidiscontinuities, Experianomalies and Awaretheory" />
    </pages>
  </query>
</api>