Kohler, Littleton, author
State University , 1951
Buku Teks
edited by Gregory A. Kimble, Michael Wertheimer, Charlotte White
American Psychological Association, 1991
Buku Teks
Berndt, Catherine H., author
Pitman, 1983
Buku Teks
Cramer, John, author
Allen & Unwin, 1989
Buku Teks
Bower, John Z.
John Hapkins Press,, 1970
Buku Teks