Capon, Claire, author
Prentice-Hall, 2000
Buku Teks
Chusway, Barry
Elex Media Komputindo, 1995
Buku Teks
George, Jennifer M., author
Prentice Hall,, 2002
Buku Teks
Umstot, Denis D
West, 1984
Buku Teks
McKenna, Eugene, author
Psychology Press, 2000
Buku Referensi