Keedy, Mervin L.
Addison-Wesley, 1986
Buku Teks
Robertson, S. Ian
Psychology Press, 2001
Buku Teks
Billstein, Rick
Pearson Addison Wesley, 2007
Buku Teks
Snover, Stephen L.
Prentice-Hall, 1982
Buku Teks
edited by Janet Davidson, Robert J. Sternberg
Cambridge university , 2003
Buku Teks