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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>
    <alltransclusions gatcontinue="Bootparm|1352" />
  </query-continue>
  <query>
    <pages>
      <page pageid="728" ns="12" title="Help:Editing" />
      <page pageid="737" ns="0" title="Installing LFS on a ThinkPad T23" />
      <page pageid="1032" ns="0" title="Ipw2200" />
      <page pageid="1142" ns="0" title="Problem with high power drain in ACPI sleep" />
      <page pageid="1143" ns="0" title="How to make APM work" />
      <page pageid="1144" ns="0" title="How to make ACPI work" />
      <page pageid="1152" ns="0" title="Kernel parameters" />
      <page pageid="1176" ns="0" title="Problem with high pitch noises" />
      <page pageid="4080" ns="0" title="Table of thinkpad-acpi LEDs" />
    </pages>
  </query>
</api>