Emerald, 2016
eBooks
Bittel, Lester Robert, author
Addison-Wesley Publishing Company, Inc., 1987
Buku Teks
Coates, Dennis E., author
American Society for Training & Development, 2007
eBooks
Disna Gusmaladevi, author
Fakultas Psikologi Universitas Indonesia, 2001
UI - Tesis (Membership)
Biech, Elaine, author
ASTD press, 2009
Buku Teks