edited by J. Graham Beaumont
Grange Books, 1989
Buku Referensi
Levitin, Daniel J.
Dutton, 2006
Buku Teks SO
Lucas, Bob
American Management Association, 2008
eBooks
Brogan, Kelly
Thorson, 2016
Buku Teks SO
Post, Karen
[American Management Association, ], 2004
eBooks