Q- was that 4, 5 and 6 of the 1971 edition? How much variation do you find in the contents of the Silver Burdett books? I've seen citations for 1964, 1965 and 1968 editions at Worldcat and I guess if it's not really in the 1971 edition as indicated by the (invisible) U Michigan digital edition, it could be in one of the earlier ones? So frustrating, not being able to see the index even of that book online. I guess this is a job for InterLibrary Loan.