Carlson, Neil R.
Allyn and Bacon , 1997
Buku Teks SO
Santrock, John W.
W.C. Brown Publisher, 1991
Buku Referensi
Passer, Michael W.
McGraw-Hill, 2007
Multimedia
edited by Sigmund Koch, David E. Leary
APA, 2006
Buku Teks SO
Carlson, Neil R.
Allyn and Bacon, [date of publication not identified]
Buku Teks