DeWitt, Anthony L., author
Jones & Bartlett Learning, 2010
Buku Teks
Ward, Francine, author
American Society for Training & Development, 2007
eBooks
Stead, Alan, author
Facet Publishing, 2008
Buku Referensi
Sinke, Marjorie J.
Kluwer law and Taxation Publishers, 1990
Buku Teks
Nichilson, Mary Jo
Prentice-Hall, 1997
Buku Teks