Matches any pattern defined in an external schema
href attribute points to the external schema
<?xml version="1.0"?>
<SONG>
<TITLE>Hot Cop</TITLE>
<COMPOSER>Jacques Morali</COMPOSER>
<COMPOSER>Henri Belolo</COMPOSER>
<COMPOSER>Victor Willis</COMPOSER>
<PRODUCER>Jacques Morali</PRODUCER>
<PUBLISHER>PolyGram Records</PUBLISHER>
<LENGTH>6:20</LENGTH>
<YEAR>1978</YEAR>
<ARTIST>Village People</ARTIST>
<DESCRIPTION>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>The schema requires this</title>
</head>
<body>
<p>
A catchy little ditty that never achieved the
success of <cite>YMCA</cite> or <cite>In the Navy</cite>.
</p>
</body>
</html>
</DESCRIPTION>
</SONG>