XML doc wont validate

[admin]

I have an XML document:

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href=http://www.webdeveloper.com/forum/archive/index.php/"cswk.xsl"?>

<references>
<article name="Baker 2005" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="cswk.xsd">
<title>Emerging grid standards</title>
<author>C. and Brown, J., Baker, M. and Apon, A. and Ferner</author>
<year>2005</year>
<month>April</month>
<journal>Computer</journal>
<volume>38</volume>
<pages>43-50</pages>
<doi>10.1109/MC.2005.124</doi>
<owner>mab</owner>
<timestamp>2006-10-22</timestamp>
</article>

<article name="Baker 2005">
<title>Emerging grid standards</title>
<author>C. and Brown, J., Baker, M. and Apon, A. and Ferner</author>
<year>2005</year>
<month>April</month>
<journal>Computer</journal>
<volume>38</volume>
<pages>43-50</pages>
<doi>10.1109/MC.2005.124</doi>
<owner>mab</owner>
<timestamp>2006-10-22</timestamp>
</article>
</references>

and the schema is:

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

<xs:element name="references">
<xs:element name="article">
<xs:complexType>
<xs:sequence>

<xs:element name="title" type="xs:string"/>
<xs:element name="author" type="xs:string" minOccurs="0"
maxOccurs="unbounded"/>
<xs:element name="year" type="xs:integer"/>
<xs:element name="month" type="xs:string"/>
<xs:element name="journal" type="xs:string"/>
<xs:element name="volume" type="xs:integer"/>
<xs:element name="pages" type="xs:string"/>
<xs:element name="doi" type="xs:string"/>
<xs:element name="owner" type="xs:string"/>
<xs:element name="timestamp" type="xs:date"/>
</xs:sequence>
<xs:attribute name="name" type="xs:string"/>
</xs:complexType>
</xs:element>
</xs:element>
</xs:schema>

Any ideas??

Thanks