<xsl:apply-templates select="composer">
         <xsl:sort select="name/last_name" order="ascending" lang="en" data-type="text"/>
         <xsl:sort select="name/first_name"/>
         <xsl:sort select="name/middle_name"/>
       </xsl:apply-templates>
data-type:
  
text
number
qualified name
lang:
  
en
fr
fr-CA
ch
etc.
order:
  
ascending
descending
case-order:
  
upper-first
lower-first