Ogden, Jane
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Buku Teks
The American Psychological Association,
Majalah, Jurnal, Buletin
DiMatteo, M. Robin
Allyn and Bacon, 2002
Buku Teks
Sheridan, Charles L.
John Wiley & Sons, 1992
Buku Teks
Edited by S. Maes, H. Leventhal and M. Johnston
John Wiley & Sons, 1993
Buku Teks