Whiteman, Thomas, author
Zondervan, 1996
Buku Teks
Davenport, Dawn, author
Broadway Books, 2006
Buku Teks
Peurifoy, Reneau Z., author
Warner Books, 2005
Buku Teks
Richman, Larry, author
[American Management Association, ], 2002
eBooks
Entrepreneur Press, Ciree Linsenman
Entepreneur Press, 2011
Buku Teks