Broughton, Philip Delves, author
The Penguin Press, 2012
Buku Teks
Fisher, James R., author
Elex Media Komputindo, 1994
Buku Teks
Johnson, Winslow, author
[American Management Association, ], 2004
eBooks
Carrison, Dan, author
[American Management Association, ], 1999
eBooks
Rogers, David J., author
Charles Schribder's Sons, 1987
Buku Teks