Bruce Michael Bagley, Roberto Alvarez, and Katherine J. Hagedorn, editors
Westview Press, 1985
Buku Teks
Miller, William
Prentice-Hall, 1964
Buku Teks
Viorst, Milton
Chilton Book, 1965
Buku Teks
Viorst, Milton
Chilton Books, 1965
Buku Teks
Phillip R.Trimble
Aspen Law & Business, 1999
Buku Teks