Umland, Jean B., author
Brooks/Cole, 1999
Buku Teks
Paul, Martin A., author
Harcourt, Brace & World, 1967
Buku Teks
Brady, James E., author
John Wiley & Sons, 1978
Buku Teks
Brady, James E., author
John Wiley & Sons, 1982
Buku Teks
Keenan, Charles W., author
Harper and Row, 1966
Buku Teks