Christensen, Larry B., 1941-, author
Boston Allyn and Bacon 1988,
Buku Referensi
American Psychological Association, 2018
Majalah, Jurnal, Buletin
the American Psychological Association, 2018
Majalah, Jurnal, Buletin
Myers, Anne, author
Wadsworth and Cengage Learning, 2012
Buku Teks
Plutchik, Robert
Harper & Row , 1983
Buku Teks