Crum, William Leonard
University of California Press, 1953
Buku Teks SO
Maynard, Lee
New York Washington Square Press 1988
Buku Teks
McCarty, F. William.
Richard D. Irwin, 1993
Buku Teks
McCarty, F. William.
Richard D. Irwin, 1990
Buku Teks
Hammer, Lawrence H.
South-Western Pub. Co, 1994
Buku Teks