Something like this:
<xsl:template match="ns0:mapping01s_mt" xmlns:ns0=...>
<xsl:copy>
<xsl:apply-templates select="maproot/b01"/>
</
</
<xsl:template match="b01">
<mapping>
<xsl:copy-of select=" ../h01 | ../h02 | * "/>
</
</
Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference