Robertson, S. Ian
Psychology Press, 2001
Buku Teks
Eide, Arvid R.
McGraw-Hill, 2002
Buku Teks
Fogler, H. Scott
Prentice-Hall, 2008
Buku Teks
edited by Janet Davidson, Robert J. Sternberg
Cambridge university , 2003
Buku Teks
Dayton, C. Mitchell
McGraw-Hill, 1971
Buku Teks