Siyan, Karanjit, author
New Riders, 1995
Buku Teks
Chichi Shintia Laksani, author
Fakultas Eknonomi dan Bisnis Universitas Indonesia, 2010
UI - Tesis (Open)
Umar Basalim, author
Pustaka Indonesia Satu, 2002
Buku Teks
Nagel, christian, author
Wiley Publishing, inc., 2010
Buku Teks
Hinkle, Deborah A., author
Glencoe McGraw-Hill, 1998
Buku Teks