I'm building XSLT files to transfomr XML data to XML Excel spreadsheet files,

From the worksheet that I created with the XML data I am taking the data and
creating another worksheet with pivot table, the problem is that this
requiring except the source worksheet name the file name too... ?!

somthing like [XSL Output.xml]Report Data

The problem is that the file name is not static and it could change from
time to time... so...

Is there a way to tell Excel too look for the worksheet in the current file ?
Is there a workaround for this problem ?