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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>
    <links gplcontinue="1|0|Pierre_Gagnon_(1572)" />
  </query-continue>
  <query>
    <pages>
      <page pageid="18" ns="0" title="Alexandre Gagnon (1844)" contentmodel="wikitext" pagelanguage="en" touched="2017-05-03T20:01:07Z" lastrevid="1278" counter="6623" length="1274" />
      <page pageid="17" ns="0" title="Alexandre Gagnon (1865)" contentmodel="wikitext" pagelanguage="en" touched="2016-04-14T05:40:01Z" lastrevid="1287" counter="21787" length="3787" />
      <page pageid="6" ns="0" title="Barnabé Gagnon (1547)" contentmodel="wikitext" pagelanguage="en" touched="2017-05-03T20:01:07Z" lastrevid="191" counter="15114" length="808" />
      <page pageid="21" ns="0" title="Dominique Gagnon (1730)" contentmodel="wikitext" pagelanguage="en" touched="2017-05-03T20:01:07Z" lastrevid="103" counter="4153" length="493" />
      <page pageid="20" ns="0" title="Dominique Gagnon (1755)" contentmodel="wikitext" pagelanguage="en" touched="2017-05-03T20:01:07Z" lastrevid="112" counter="4693" length="746" />
      <page pageid="305" ns="0" title="Gagnon Family History" contentmodel="wikitext" pagelanguage="en" touched="2017-07-20T18:15:16Z" lastrevid="1334" counter="9542" length="57216" />
      <page pageid="24" ns="0" title="Jean Gagnon (1610)" contentmodel="wikitext" pagelanguage="en" touched="2017-05-03T19:35:55Z" lastrevid="1320" counter="12034" length="2429" />
      <page pageid="23" ns="0" title="Jean Gagnon (1648)" contentmodel="wikitext" pagelanguage="en" touched="2017-05-03T20:01:07Z" lastrevid="1237" counter="6746" length="710" />
      <page pageid="22" ns="0" title="Joseph Gagnon (1685)" contentmodel="wikitext" pagelanguage="en" touched="2017-05-03T20:01:07Z" lastrevid="1235" counter="4091" length="503" />
      <page pageid="16" ns="0" title="Onesime Gagnon (1892)" contentmodel="wikitext" pagelanguage="en" touched="2016-04-21T03:58:15Z" lastrevid="1300" counter="69884" length="39511" />
    </pages>
  </query>
</api>