I want to combine three cells with 'Concatenate' function and get the result
like

cell A1 = 10 (emp code)
cell B1 = filename.xls
cell C1 = sheet1'!A1

my coding is

=concatenate(a1,b1,c1) --- it should show the content of cell A1 in
10filename.xls , since the A1 is changeable.

rpmani