Getting data for a workbook from another workbook conditionally
 

I want to create a new workbook from a variable number of othe workbooks,
that is not the problem. The problem is the data for the new wookbook could
be on either of 2 different sheets in the input workbooks.
=if('c:\[ws1.xls]shhet1A1="",'c:\[ws1.xls]sheet2A!,'C:\[ws1.xls]sheet1A!)
doesn't work. Help
Hardy