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Perseus Books, 2000
Buku Teks
Marquardt, Michael, author
[American Society for Training and Development Press;;, ], 2005
eBooks
Samperuru, Maria A., author
Fakultas Psikologi Universitas Indonesia, 2002
UI - Tesis (Membership)
Kirk, James J., author
McGraww-Hill, 1997
Buku Teks
Artikel Jurnal