Still, Richard R.
Prentice Hall International, 1988
Buku Teks
Ohai, Tim
American Society for Training & Development, 2008
eBooks
Battersby, Albert
Penguin Books, 1968
Buku Teks
Sugars, Bradley J.
McGraw-HIll , 2006
Buku Teks
Mikula, Jim
American Society for Training and Development Press;, 2004
eBooks