Sinaga, Ronald, author
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2004
UI - Tesis (Membership)
Phillips, Patricia Pulliam, author
American Society for Training & Development, 2012
eBooks
Hanan, Mack
McGraw-Hill, 1987
Buku Teks
Harvard Business School , 2000
Buku Teks
[compiled by] John A. Pearce II, Richard B. Robinson, Jr.
McGraw-Hill, 1987
Buku Teks