<?xml version="1.0"?>

<xsl:stylesheet 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  version="1.0">

  <xsl:output method = "text"/>

  <xsl:param name="properties"/>

  <xsl:variable name="who">
    <xsl:apply-templates select="document($properties)/Properties/NameValue[Name='who']/Value"/>
  </xsl:variable>

  <xsl:template match="Document">
    <xsl:apply-templates/><xsl:value-of select="$who"/>
  </xsl:template>

</xsl:stylesheet>