Porter, Donald E., author
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Buku Teks
Kolb, David A., author
Prentice-Hall, 1984
Buku Teks
Honour, T. F., author
Bina Aksara, 1982
Buku Teks
edited by Pieter J.D. Drenth, Henk Thierry, Charles J. de Wolff
Routledge, 1998
Buku Referensi
edited by Pieter J.D. Drenth, Henk Thierry, Charles J. de Wolff
Psychology Press, 1998
Buku Referensi