The tag "<xsl:key name="by-id" match="Att[@Ty='TM']" use="@Id"/>" is working fine with single input xml file. But i have issues in multiple input xml file. Is it possible to handle the multiple input xml in <xls:key ...? such as

<xsl:key name="by-id" match="document(/Envelope/Part/@File)/Invoice/InvoiceItem/AggSet/Att[@Ty='TM']" use="@Id"/>

i am getting ERROR: 'Syntax error in 'document(/Envelope/Part/@File)/Invoice/InvoiceItem/AggSet/Att[@Ty='TM']'.'

[u]All input xml file defined in one single xml file as follows,</u><?xml version="1.0" encoding="UTF-8"?>
<Envelope>
<Part File='TestJS.xml' LinkType='REL' DocType='INV' Format='XML'/>
</Envelope>

Please find more details as follows,

<xsl:key name="by-id" match="Att[@Ty='TM']" use="@Id"/>

<xsl:for-each select="/Document/Invoice/InvoiceItem/AggSet/Att[@Ty='TM'][generate-id() = generate-id(key('by-id', @Id)[1])]"> *****1*****
 Invoked....
</xsl:for-each>

If i used doucment() to load the xml file, its not working such as

<xsl:for-each select="document(/Envelope/Part/@File)/Document/Invoice/InvoiceItem/AggSet/Att[@Ty='TM'][generate-id() = generate-id(key('by-id', @Id)[1])]"> *****1*****
     Not Working...
</xsl:for-each>