Brained, Walter S., author
Boyd & Fraser publishing company, 1986
Buku Teks
Brainerd, Walter S., author
Boyd & Fraser Publishing Company, 1986
Buku Teks
Merchant, Michael J., author
Wadsworth, 1977
Buku Teks
Kreitzberg, Charles B., author
Harcourt Brace Javanovich, 1982
Buku Teks
Kennedy, Michael, author
Prentice-Hall, 1975
Buku Teks