> > <xsl:sort select="
> >    monogr/author |
> >    self::*[not(monogr/author)]/analytic/author |
> >    self::*[not(monogr/author | analytic/author)]/monogr/editor |
> >    self::*[not(monogr/author | analytic/author | 
> > monogr/editor)]/monogr/title"/>
> 
> I think for XSLT 1.0 you can simplify that select to:
> 
> <xsl:sort select="(monogr/author|analytic/author)[1]"/>
> 

I don't think so. That will select the first in document order, not the
first in the order of precedence defined in the requirement statement.

Michael Kay
http://www.saxonica.com/