Wilson, Charles E., author
Harper & Row , 1989
Buku Teks
Elgar, Peter
Prentice-Hall, 1998
Buku Teks
Garner, K.C., author
Pergamon Press, 1968\
Buku Teks
Gilley, Jerry W., author
[American Society for Training and Development Press, American Society for Training and Development Press], 2005
eBooks
Dunn, Patrick F.
McGraw-Hill, 2005
Buku Teks