Maybe,

=SUM(Sheet1:Sheet3!A1)+SUM(Sheet1:Sheet3!B1)

Obviouslt change 3 to 10.

Mike

"rob" wrote:

I do have about 10 sheets with data.
I want to have the sum of products of two identical cells in each sheet.

something like:
sumproduct(sheet1:sheet10!a1,sheet1:sheet10!b1)
which should return me the sum of 10 products.

However I do get a #ref error.

Any other solution?