Morrisey, George L., author
Addison-Wesley, 1987
Buku Teks
Munter, Mary
Prentice-Hall, 2002
Buku Teks
Leech, Thomas, author
[American Management Association, ], 2004
eBooks
Lindstrom, Robert L.
McGraw-Hill , 1994
Buku Teks
Brusino, Justin, author
American Society for Training & Development, 2008
eBooks