Buchbinder, Sharon B.
Jones and Bartlett Learning, 2014
Buku Teks
Kotler, Philip
Prentice-Hall, 1987
Buku Teks
MacStravic, Robin E.
Aspen Publication, 1977
Buku Teks
Berkowitz, Eric N.
Jones & Bartlett Learning, 2017
Buku Teks
edited by Charles D. Schewe
Haworth Press, 1991
Buku Teks