If C16 and C42 contain values, then all you need is =C16+C42 [or you can use
=SUM(C16,C42), but you don't need =SUM(C16+C42)].

What formula do you have in C16, and in C42? If C16 is something like
=6th!F46, then it should work provided that 6th!F46 contains a value. You
may need to trace on back through the chain to see whereabouts you don't
have a value.
--
David Biddulph

"Labman1366" wrote in message
...
I am trying to add the values of two cells which contain links to other
worksheets. Can I do that and how? (Ex.: Cell C6 equation
=SUM(C16+C42).
Cell C16 is linked to Cell f46 of worksheet 6th while Cell C42 is linked
to
Cell F46 of worksheet 8th. A "value" does not appear in either cell as
far
as my equation can tell. How do I get Excel to add the values of the two
cells?