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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|Nuclear_and_Particle_Experiment" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1282" ns="0" title="Astrophysics" contentmodel="wikitext" pagelanguage="en" touched="2011-03-16T17:49:31Z" lastrevid="1600" counter="957" length="740" />
      <page pageid="1332" ns="0" title="Atomic and Optical Physics" contentmodel="wikitext" pagelanguage="en" touched="2013-03-28T17:11:55Z" lastrevid="1634" counter="160" length="6347" />
      <page pageid="1311" ns="0" title="Biophysics" contentmodel="wikitext" pagelanguage="en" touched="2012-05-15T19:42:46Z" lastrevid="1630" counter="250" length="1895" />
      <page pageid="1323" ns="0" title="Condensed Matter Experiment" contentmodel="wikitext" pagelanguage="en" touched="2009-04-16T19:31:09Z" lastrevid="1548" counter="190" length="240" />
      <page pageid="1305" ns="0" title="Condensed Matter Theory" contentmodel="wikitext" pagelanguage="en" touched="2008-03-12T16:35:58Z" lastrevid="1367" counter="225" length="304" new="" />
      <page pageid="1316" ns="0" title="General Exam Part 1" contentmodel="wikitext" pagelanguage="en" touched="2008-06-06T19:07:48Z" lastrevid="1393" counter="64" length="197" new="" />
      <page pageid="1317" ns="0" title="General Exam Part 2" contentmodel="wikitext" pagelanguage="en" touched="2008-06-06T19:08:05Z" lastrevid="1394" counter="71" length="197" new="" />
      <page pageid="1319" ns="0" title="General Exam Part 3" contentmodel="wikitext" pagelanguage="en" touched="2013-03-28T17:10:11Z" lastrevid="1596" counter="995" length="622" />
      <page pageid="1333" ns="0" title="General Resources" contentmodel="wikitext" pagelanguage="en" touched="2015-03-06T22:01:51Z" lastrevid="1640" counter="12" length="502" new="" />
      <page pageid="1334" ns="0" title="MIT Resources" contentmodel="wikitext" pagelanguage="en" touched="2015-03-06T22:20:46Z" lastrevid="1641" counter="9" length="1506" new="" />
    </pages>
  </query>
</api>