have this xml database feed:
<RECORD>
<page_id>products_a</page_id>
<label>brochure</label>
<code>nl</code>
</RECORD>
<RECORD>
<page_id>products_a</page_id>
<label>brochure</label>
<code>fr</code>
</RECORD>
<RECORD>
<page_id>products_a</page_id>
<label>leaflet</label>
<code>nl</code>
</RECORD>
<RECORD>
<page_id>products_b</page_id>
<label>leaflet</label>
<code>nl</code>
</RECORD>
<RECORD>
<page_id>products_b</page_id>
<label>leaflet</label>
<code>fr</code>
</RECORD>

result must be
product a
- brochure: nl, fr
- leaflet: nl
product b
- leaflet: nl, fr

Figured already out how to sort by <product>, but struggling on how to sort in next level, first by <label>, and list for each different <label> all <code>

I have already this for the first level:

<xsl:key name="item-by-product" match="RECORD" use="page_id"/>
[list]
<xsl:for-each select="PAGE/CONTENT/DB/RECORDS[@label = 'downloadsall']/RECORD[count(. | key('item-by-product',page_id)[1]) = 1]">
<li><xsl:value-of select="page_id"/></li>
<xsl:value-of select="page_id"/>
</xsl:for-each>
</ul>

within <li> should start the second loop ...