see muenchian grouping

<xsl:key name="k" match="xsd:element" use="concat(@name,' ',@type)"/>

<xsl:template match"/">
<uniqueElements>
<xsl:for-each
select="//xsd:element[generate-id()=generate-id(key('k',concat(@name,' ',@type)))]">
<xsl:copy>
<xsl:copy-of select="@name|@type"/>
</xsl:copy>
</xsl:for-each>
</uniqueElements>
</xsl:template>

should be all you need.

David

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