American Psychological Association, 2018
Majalah, Jurnal, Buletin
Myers, Anne, author
Wadsworth and Cengage Learning, 2012
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Kantowitz, Barry H., author
Cengage Learning, 2015
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the American Psychological Association, 2018
Majalah, Jurnal, Buletin
Kaplan, Abraham, author
Chandler, 1964
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