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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"?>
    <allfileusages gafcontinue="Change-avatar.jpeg|161" />
      <page pageid="173" ns="0" title="Enabling ReCaptcha" />
      <page pageid="338" ns="0" title="Event Calendar Distorted" />
      <page pageid="492" ns="0" title="Jomsocial 2 System Requirements" />
      <page pageid="681" ns="0" title="Setup your own server for 5$ a month" />
      <page pageid="812" ns="0" title="Add the custom element based on the Joomla User Group" />
      <page pageid="829" ns="0" title="JS Hello Me" />
      <page pageid="868" ns="0" title="JS Toolbar" />
      <page pageid="869" ns="0" title="JS Birthday" />