Stewart, Valerie, author
McGraw-Hill, 1983
Buku Teks
Helms-Mills, Jean, author
Routledge, 2009
Buku Teks
Garber, Peter R., author
American Society for Training & Development, 2012
eBooks
Harvard Business School Press, 1998
Buku Teks
John, E.A., author
Pergamon, 1973
Buku Teks