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HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
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<?xml version="1.0"?>
<api>
  <query>
    <pages>
      <page ns="0" title="API" missing="" />
      <page pageid="1" ns="0" title="Main Page">
        <revisions>
          <rev user="Admin" timestamp="2007-01-03T17:17:57Z" comment="" contentformat="text/x-wiki" contentmodel="wikitext" xml:space="preserve">== Welcome to our Genealogy Wiki ==

This section of the site will allow you to browse more detailed information on the people and places associated with our family tree.
If you have registered and received an account, then you will be able to login here with that account as well.  Logging in will allow you access to protected pages, and also allow you to add and edit pages as well.

*[[:Category:Places|List of Settlements and their History]]
*[[:Category:People|List of Family Stories and their History]]</rev>
        </revisions>
      </page>
    </pages>
  </query>
</api>