Hoy, Anita Woolfolk, 1947-, author
Allyn and Bacon, 2004
Buku Teks
Witherington, H.C., author
Aksara Baru, 1978
Buku Teks
the American Psychological Association, 2018
Majalah, Jurnal, Buletin
Wilson, John A. R., author
McGraw-Hill, 1974
Buku Teks
Pedro Isaias, editors
Springer, 2012
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