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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>
    <allimages gaicontinue="Charting_A_Circle.JPG" />
  </query-continue>
  <query>
    <pages>
      <page pageid="5198" ns="6" title="File:2dGridReproduction small 4by5.gif" />
      <page pageid="5200" ns="6" title="File:3dGridReproduction 3 8 6.gif" />
      <page pageid="2245" ns="6" title="File:A proof that C-0,1- is not complete with the 2-norm.pdf" />
      <page pageid="521" ns="6" title="File:Angular chart on a circle.JPG" />
      <page pageid="1551" ns="6" title="File:AttachingC2Part2.JPG" />
      <page pageid="3059" ns="6" title="File:Base5.jpg" />
      <page pageid="1553" ns="6" title="File:C1JoinResult.JPG" />
      <page pageid="1550" ns="6" title="File:C2JoinPart1.JPG" />
      <page pageid="1552" ns="6" title="File:C2JoinResult.JPG" />
      <page pageid="2147" ns="6" title="File:CauchySequenceOfNthsTermsOfCauchySequenceInEllpProof.jpg" />
    </pages>
  </query>
</api>