McGovern, Edmond, author
Globefield Press, 1982
Buku Teks
Czinkota, Michael R., author
The Dryden Press, 1994
Buku Teks
Friedland, Jerold A., author
Lexis, 2014
Buku Teks
Fritscher, A. Lee
Little, Brown & Co., 1980
Buku Teks
The Foundation Press, Inc., 1975
Buku Teks