воспользоваться атрибутами doctype-system и doctype-public элемента <xsl:output>. Вот пример элемента <xsl:output>, создающего элемент <!DOCTYPE> для переходного XHTML 1.0:
<xsl:output method='xml'
doctype-system='http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd'
doctype-public='-//W3C//DTD XHTML 1.0 Transitional//EN'
indent='yes'/>
В листинге 6.5 приведена полная таблица стилей planets.html, использующая этот элемент <xsl:output> для преобразования planets.xml в допустимый документ XHTML.
<?xml version='1.0'?>
<xsl:stylesheet version='1.0'
xmlns:xsl='http://www.w3.org/1999/XSL/Transform'>
<xsl:output method='xml'
doctype-system='http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd'
doctype-public='-//W3C//DTD XHTML 1.0 Transitional//EN'
indent='yes'/>
<xsl:template match='/PLANETS'>
<html>
<head>
<title>
The Planets Table
</title>
</head>
<body>
<h1>
The Planets Table
</h1>
<table>
<tr>
<td>Name</td>
<td>Mass</td>
<td>Radius</td>
<td>Day</td>
</tr>
<xsl:apply-templates/>
</table>
</body>
</html>
</xsl:template>
<xsl:template match='PLANET'>
<tr>
<td><xsl:value-of select='NAME'/></td>
<td><xsl:apply-templates select='MASS'/></td>
<td><xsl:apply-templates select='RADIUS'/></td>
<td><xsl:apply-templates select='DAY'/></td>
</tr>
</xsl:template>
<xsl:template match='MASS'>
<xsl:value-of select='.'/>
<xsl:text> </xsl:text>
<xsl:value-of select='@UNITS'/>
</xsl:template>
<xsl:template match='RADIUS'>
<xsl:value-of select='.'/>
<xsl:text> </xsl:text>
<xsl:value-of select='@UNITS'/>
</xsl:template>
<xsl:template match='DAY'>
<xsl:value-of select='.'/>
<xsl:text> </xsl:text>
<xsl:value-of select='@UNITS'/>
</xsl:template>
</xsl:stylesheet>
Вот результирующий файл XHTML:
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE html
PUBLIC '-//W3C//DTD XHTML 1.0 Transitional//EN'
'http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd'>
<html>
<head>
<title>
The Planets Table
</title>
</head>
<body>
<h1>
The Planets Table
</h1>
<table>
<tr>
<td>Name</td>
<td>Mass</td>
<td>Radius</td>
<td>Day</td>
</tr>
<tr>
<td>Mercury</td>
<td>.0553 (Earth = 1)</td>
<td>1516 miles</td>
<td>58.65 days</td>
</tr>
<tr>
<td>Venus</td>
