Xml-xsl

can anyone tell me how can i include <?xml-stylesheet type="text/css" href="page3.css"/?> in the XSL file in order to come out in the output file?

for example i have this:

<?xml version='1.0'?>
<xsl:stylesheet version="1.0" xmlnssl="http://www.w3.org/1999/XSL/Transform">
<?xml-stylesheet type="text/css" href="page3.css"/?>
<xsl:template match="users">
<page3>
<registered>
<title>Registered</title>
<gift>
<header1>User's Full Name</header1>
<header2>Gift Name</header2>
</gift>
<xsl:for-each select="user/giftR">
<xsl:if test='purchased="no"'>
<gift>
<user>
<xsl:value-of select="../fullname"/>
</user>
<giftname>
<xsl:value-of select="name"/>
</giftname>
</gift>
</xsl:if>
</xsl:for-each>
</registered>

but <?xml-stylesheet type="text/css" href="page3.css"/?> is ommited on the output and i need it so that the xml output is displayed nicely with css2

thanks