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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>
    <embeddedin eicontinue="10|Stub|216" />
  </query-continue>
  <query>
    <embeddedin>
      <ei pageid="44" ns="100" title="Glossary:Panic Architecture" />
      <ei pageid="71" ns="0" title="Cyberspace: First Steps" />
      <ei pageid="81" ns="0" title="Howard Rheingold" />
      <ei pageid="83" ns="0" title="Michael Benedikt" />
      <ei pageid="90" ns="0" title="Between Nature &amp; Culture Cyborgs, Simians, Dogs, Genes &amp; Us" />
      <ei pageid="91" ns="0" title="The Cell Phone: An Anthropology of Communication" />
      <ei pageid="92" ns="0" title="A New Set of Social Rules for a Newly Wireless Society" />
      <ei pageid="93" ns="0" title="Reassembling the Social: An Introduction to Actor-Network-Theory" />
      <ei pageid="116" ns="0" title="Sensorium: Embodied Experience, Technology, and Contemporary Art" />
      <ei pageid="121" ns="0" title="Understanding Media: The Extensions of Man" />
    </embeddedin>
  </query>
</api>