Chalos, Peter
Prentice-Hall, 1992
Buku Teks
Massachusetts Harvard Business School Press, 1988
Buku Teks
Nicholson, T.A.J., author
Macmillan, 1978
Buku Teks
Christie, Linda Gail, author
Jones-Irwin, 1986
Buku Teks
edited by Tensie Whelan; foreword by Peter A. A. Berle
New York : Uslan Press, 1991,
Buku Referensi