Artikel Jurnal
Fox, Scott C., author
[American Management Association, ], 2012
eBooks
Cheeseman, Henry R., author
Pearson - Prentice Hall, 2006
Buku Teks
edited by Mary J. Cronin
Harvard Business School Press , 1996
Buku Teks
Emery, Vince
Dinastindo , 1997
Buku Teks