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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>
    <unreviewedpages>
      <p pageid="816" ns="0" title="Coming from flood forecasts to emergency response mesures (workshop 04.11.2016 in Tiel)" revid="3579" under_review="" />
      <p pageid="4" ns="0" title="Faalmechanisme" revid="4750" under_review="" />
      <p pageid="5" ns="0" title="Macro instabiliteit" revid="401" under_review="" />
      <p pageid="1" ns="0" title="Main Page" revid="2570" under_review="" />
      <p pageid="11" ns="0" title="Noodmaatregelen" revid="4742" under_review="" />
      <p pageid="19" ns="0" title="Opbarsten" revid="2787" under_review="" />
      <p pageid="18" ns="0" title="Piping (STP)" revid="394" under_review="" />
      <p pageid="3" ns="0" title="Scheur" revid="2571" under_review="" />
      <p pageid="13" ns="0" title="Stabilisatie binnentalud met steunberm" revid="2816" under_review="" />
      <p pageid="12" ns="0" title="Steunen binnentalud met zandzakken" revid="3758" under_review="" />
    </unreviewedpages>
  </query>
</api>