Hi Ken,
Yes, only one attribute to either element.

You said:
xsl:copy-of select="( ../Location[name(@*)=name(current()/@*)] ,
                    ../Location/@denomination ,
                    '0' )[1]"/>

but I may have explained my needs incorrectly. Your statement works on the first example below [uses @denomination] but returns nothing for the second example; there it should return the value of the <Locations @souvenir-sheet>, i.e., '1'.

~/t/ftemp $ cat mark.xml
<Stamps>
 <Stamp>
       <Formats souvenir-sheet="2895"/>
     <Location denomination="1"/>
</Stamp>

<Stamp>
      <Formats souvenir-sheet="2896"/>
     <Location denomination="5"/>
     <Location souvenir-sheet="1"/>
   </Stamp>
</Stamps>~/t/ftemp $ cat mark.xsl
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  version="2.0">
  <xsl:output indent="yes"/>
  <xsl:template match="/">
    <xsl:for-each select="//Formats">
      <result>
      <xsl:copy-of select="( ../Location/@*[name(.)=name(current()/@*)] ,
                             ../Location/@denomination,
                             '0' )[1]"/>
      </result>
    </xsl:for-each>
  </xsl:template>
</xsl:stylesheet>~/t/ftemp $ xslt2 mark.xml mark.xsl
<?xml version="1.0" encoding="UTF-8"?>
<result denomination="1"/>
<result souvenir-sheet="1"/>~/t/ftemp $

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