Haber, Ralph Norman
Holt, Rinehart and Winston, 1966
Buku Teks
Peterson, Robert A., author
Business Publications , 1982
Buku Teks
Danah Zohar, author
Mizan, 2005
Buku Teks
Anya Safira, author
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2013
UI - Skripsi (Membership)
Preston, Lee E., author
IBER (Institute of Business and Economic Research), 1966
Buku Teks