Batra, Ravi
Simon and Schuster , 1988
Buku Teks
Kiyosaki, Robert T., 1947-, author
Gramedia Pustaka Utama, 2003
Buku Teks
American Bar Association
Publications International, 1990
Buku Referensi
Lerner, Joel J., author
New York, N.Y. , McGraw-Hill
Buku Teks
Zabel, William D.
William Morrow and Company, Inc., 1995
Buku Teks