<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:fo="http://www.w3.org/1999/XSL/Format">
<xsl:variable name="label_Files" select="'Files'" /> (1)
<xsl:variable name="label_Issues">Issues</xsl:variable> (2)
...
<xsl:template>
<fo:block>
<xsl:value-of select="$label_Files" /> (3)
</fo:block>
</xsl:template>
</xsl:stylesheet>