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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>
    <allredirects garcontinue="ver4/関数リファレンス/BcBaser_content" />
  </query-continue>
  <query>
    <pages>
      <page ns="0" title="ver4/関数リファレンス/BcBaser changePrefixToAlias" missing="" />
      <page pageid="23" ns="0" title="baserCMS 利用ガイド" />
      <page pageid="24" ns="0" title="baserCMS 開発ガイド" />
      <page pageid="109" ns="0" title="baserCMS公式ガイドとは" />
      <page pageid="589" ns="0" title="ver4/関数リファレンス/BcBaser addCrumb" />
      <page pageid="590" ns="0" title="ver4/関数リファレンス/BcBaser baseUrl" />
      <page pageid="591" ns="0" title="ver4/関数リファレンス/BcBaser blogPosts" />
      <page pageid="592" ns="0" title="ver4/関数リファレンス/BcBaser cacheHeader" />
      <page pageid="594" ns="0" title="ver4/関数リファレンス/BcBaser charset" />
      <page pageid="595" ns="0" title="ver4/関数リファレンス/BcBaser checkUpdate" />
    </pages>
  </query>
</api>