Carrison, Dan
AMACOM, 2005
Buku Teks SO
Johnson, Winslow
[American Management Association, ], 2004
eBooks
Tuttle, Matthew
John Wiley & Sons, 2009
Buku Teks
Hart, B.H. Liddell
George Allen and Unwin, 1946
Buku Teks SO
Sexton, John
M. Evans and Company, 1986
Buku Teks