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"?>
    <querypage qpoffset="10" />
    <querypage name="Ancientpages">
        <page value="20110919172821" timestamp="2011-09-19T17:28:21Z" ns="0" title="Instituições de pesquisa" />
        <page value="20110919172911" timestamp="2011-09-19T17:29:11Z" ns="0" title="Conferencias" />
        <page value="20110919173334" timestamp="2011-09-19T17:33:34Z" ns="0" title="Xmgrace" />
        <page value="20110919173401" timestamp="2011-09-19T17:34:01Z" ns="0" title="LaTex" />
        <page value="20110919173422" timestamp="2011-09-19T17:34:22Z" ns="0" title="FORTRAN" />
        <page value="20110919173457" timestamp="2011-09-19T17:34:57Z" ns="0" title="C" />
        <page value="20110919173658" timestamp="2011-09-19T17:36:58Z" ns="0" title="Spline cúbico" />
        <page value="20110919173716" timestamp="2011-09-19T17:37:16Z" ns="0" title="Eliminação gaussiana e retro-substituição" />
        <page value="20110919173850" timestamp="2011-09-19T17:38:50Z" ns="0" title="Integração numérica de equações diferenciais ordinárias" />
        <page value="20110919173907" timestamp="2011-09-19T17:39:07Z" ns="0" title="Métodos multipassos" />