Jacobson, Michael D., author
Routledge, 1987
Buku Teks
Kruger, Arthur N.
The Scarecrow Press, Inc., 1968
Buku Teks
Fedrizzi, Mariann, author
South Western Cengage Learning, 2011
Buku Teks
Fryar, Maridell
National Textbook Co., 1979
Buku Teks
Vancil, David L
Allyn and Bacon, 1993
Buku Teks