You are looking at the HTML representation of the XML format.
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>
    <querypage qpoffset="10" />
  </query-continue>
  <query>
    <querypage name="Ancientpages">
      <results>
        <page value="20140529131642" timestamp="2014-05-29T13:16:42Z" ns="0" title="Rok 1929" />
        <page value="20140529144448" timestamp="2014-05-29T14:44:48Z" ns="0" title="Rok 1923" />
        <page value="20140529144559" timestamp="2014-05-29T14:45:59Z" ns="0" title="Rok 1924" />
        <page value="20140529184158" timestamp="2014-05-29T18:41:58Z" ns="0" title="Rok 1922" />
        <page value="20140531085326" timestamp="2014-05-31T08:53:26Z" ns="0" title="1930" />
        <page value="20140602080736" timestamp="2014-06-02T08:07:36Z" ns="0" title="Eugeniusz Rybka" />
        <page value="20140604130345" timestamp="2014-06-04T13:03:45Z" ns="0" title="Warszawa, Chmielna 88" />
        <page value="20140615100816" timestamp="2014-06-15T10:08:16Z" ns="0" title="1933" />
        <page value="20140615135227" timestamp="2014-06-15T13:52:27Z" ns="0" title="1935" />
        <page value="20140615142120" timestamp="2014-06-15T14:21:20Z" ns="0" title="1936" />
      </results>
    </querypage>
  </query>
</api>