McNulty, James E., author
University of Pennsylvania Press, 1964
Buku Teks
Brown, Wilfred, author
Heinemann, 1971
Buku Teks
by Lawrence L. Bethel ... [et al.]
McGraw-Hill, 1962
Buku Teks
Lawrence L. Bethel ... [et al.]
McGraw-Hill, 1945
Buku Teks
Mund, Vernon A., author
Appleton-Century-Crofts, 1971
Buku Teks