Olpin, Michael, author
Wadsworth and Cengage Learning, 2013
Buku Teks
Rivolinggo Pamudji, author
1997
UI - Skripsi (Membership)
Ahmat Dartono, author
2003
UI - Skripsi (Membership)
edited by Richard W.J. Neufeld
Wiley, 1989
Buku Teks
Boenisch, author
Grasindo, 2004
Buku Teks