Gendell, Julien, author
West Publisihing, 1993
Buku Teks
Keedy, Mervin L., author
Addison-Wesley, 1986
Buku Teks
Robertson, S. Ian, author
Psychology Press, 2001
Buku Teks
Billstein, Rick, author
Pearson Addison Wesley, 2007
Buku Teks
Snover, Stephen L., author
Prentice-Hall, 1982
Buku Teks