MacStravic, Robin E.
Aspen Publication, 1977
Buku Teks
Kotler, Philip
Prentice-Hall, 1987
Buku Teks
Fortenberry, John L., Jr.
Jones & Bartlett Learning, 2011
Buku Teks
Cleverley, William O.
Aspen Publication, 1997
Buku Teks
Hillestad, Steven G.
An Aspen Publication, 1991
Buku Teks