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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>
    <allimages gaicontinue="1DMarkIV_RangerRX_S-Head_HyperSyncOnlyDisabled_ReducedClipping.pdf" />
  </query-continue>
  <query>
    <pages>
      <page pageid="418" ns="6" title="File:1DMarkIVRangerRXS RC +3.JPG" />
      <page pageid="326" ns="6" title="File:1DMarkIV AB1600 HyperSyncOnlyDisabled HighestEnergy.pdf" />
      <page pageid="327" ns="6" title="File:1DMarkIV AB1600 HyperSyncOnlyDisabled ReducedClipping.pdf" />
      <page pageid="559" ns="6" title="File:1DMarkIV AlienBeesB1600 HighestEnergy Ver11.pdf" />
      <page pageid="558" ns="6" title="File:1DMarkIV AlienBeesB1600 ReducedClipping Ver11.pdf" />
      <page pageid="553" ns="6" title="File:1DMarkIV Einstein HighestEnergy Ver11.pdf" />
      <page pageid="552" ns="6" title="File:1DMarkIV Einstein ReducedClipping Ver11.pdf" />
      <page pageid="556" ns="6" title="File:1DMarkIV RangerRX AHead HighestEnergy Ver11.pdf" />
      <page pageid="557" ns="6" title="File:1DMarkIV RangerRX AHead ReducedClipping Ver11.pdf" />
      <page pageid="334" ns="6" title="File:1DMarkIV RangerRX S-Head HyperSyncOnlyDisabled HighestEnergy.pdf" />
    </pages>
  </query>
</api>