Stansfield, Richard H., author
The Dartnell Corporation, 1985
Buku Teks
Blanchard, Kenneth H., author
Fontana , 1983
Buku Teks
Estep, Tora, author
American Society for Training & Development, 2006
eBooks
Cleland, David I., author
McGraw-Hill, 2010
Buku Teks
Departemen Koperasi. Direktorat Jenderal Bina Lembaga Koperasi., 1987
Buku Teks