Consumers' Association and Hodder and Stoughton , 1988
Buku Teks
Keup, Erwin J.
Entrepreneur Press, 2004
Buku Teks
Mancuso, Joseph, author
Simon & Schuster , 1993
Buku Teks
Goddard, Murray C., author
Tab Books, 1977
Buku Teks
Engel, Louis
Bantam Book, 1967
Buku Teks