Forer, Lois G.
Norton, 1987
Buku Teks
Sundaram, G
Manas Publications, 2008
Buku Teks
edited by Mike Hayhoe and Stephen Parker
Open University Press, 1994
Buku Teks
Fontana, Mars Guy
McGraw-Hill, 1978
Buku Teks
Marden, Charles Frederick.
American Book Co, 1968
Buku Teks