I'm trying to sum with multiple criteria. I've been reading other postings
and tried the following with no success:

=SUMPRODUCT(--('BOM LIST'!$J$8:$J$770=B31),--('BOM
LIST'!$A$8:$A$770={"S","S-FED","O"}),--('BOM
LIST'!$G$8:$G$770={"F","Q","R"}),'BOM LIST'!$Z$8:$Z$770)

Help!

Also, can anyone recommend a book to learn such advanced formulas?