Harlow Longman , 1995
Buku Teks
Davison, Gerald C.
John Wiley & Sons, 1998
Buku Teks
edited by Anthony Gale, Michael W. Eysenck
John Wiley & Sons, 1992
Buku Referensi
Carlson, Neil R., author
Pearson/Allyn & Bacon, 2007
Buku Teks
Carlson, Neil R., author
Pearson-Prentice Hall, 2005
Buku Teks