Arnold, Thurman W.
New Haven Yale University Press 1937,
Buku Teks
Arnold, Thurman Wesley, author
Blue Ribbon Books, 1937
Buku Klasik
Boeking, Joseph
New York, N.Y. New York Duell, Sloan and Pearce 1943,
Buku Teks
Homan, Paul T.
Harcourt, Brace and Company, 1958
Buku Teks
Thurman, Harold V.
Charles E. Merrill Publishing Company, 1975
Buku Teks