Morris, Robert, author
Columbia University Press , 1966
Buku Teks
Cooper, Robert L., author
Cambridge University Press, 1989
Buku Teks
Lauer, Robert H., author
Allyn and Bacon, 1982
Buku Teks
Zaltman, Gerald, author
John Wiley & Sons, 1977
Buku Teks
Michael, Donald N.
Jossey-Bass, 1985
Buku Teks