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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>
    <allredirects garcontinue="Contrib/OpenFuelCell|3716" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1258" ns="0" title="Wmake" />
      <page pageid="1486" ns="0" title="IcoHeatFoam Blasius Flat-Plate Flow Benchmark" />
      <page pageid="1855" ns="0" title="Benchmark ercoftac urf2-02" />
      <page pageid="2511" ns="0" title="Janaf" />
      <page pageid="3041" ns="0" title="Contrib MakeAxialMesh" />
      <page pageid="3066" ns="0" title="Contrib IOReferencer" />
      <page pageid="3206" ns="0" title="ColloidalFoam" />
      <page pageid="3626" ns="0" title="LibOpenSMOKE" />
      <page pageid="3759" ns="0" title="CompressibleMixingPhaseChangeFoam" />
      <page pageid="3761" ns="0" title="Contrib electromagnetics" />
    </pages>
  </query>
</api>