> Is there any easy way of handling cross references?
> 
> I am looking to do a transform to create a legal document where each 
> paragraph is a numbered clause (handled by styles in the form 
> of 1, 2, 
> 3, 3(i), 3(ii), 3(iii)(a), 3(iii)(b), etc) and need to include a 
> facility where one clause might contain a reference to another clause 
> and the number of clauses in between might vary.
> 
> Has anyone come across this problem before/found a solution?

Sure, this is done routinely in the stylesheets that generate the W3C
specifications, and almost certainly in DocBook as well.

Suppose the target of the cross-reference is a section with an id (declared
as an ID in the DTD)

<section id="bananas">...</section>

and the cross-reference takes the form

(see <xref section="bananas"/>)

Write a template to number the sections as:

<xsl:template match="section" mode="number">
  <xsl:number level="multiple" count="book|chapter|section"
format="1(i)(a)"/>
</xsl:template>

Invoke this when processing the section:

<xsl:template match="section">
  <xsl:apply-templates select="." mode="number"/>
  <xsl:apply-templates/>
</xsl:template>

and also when processing the cross-reference:

<xsl:template match="xref">
  <xsl:apply-templates select="id(@section)" mode="number"/>
</xsl:template>

Michael Kay