1993
Buku Teks
Vesterman, William, author
[publisher not identified], [date of publication not identified]
Buku Teks
by John A. Quelch ... [and others]
Prentice-Hall, 2000
Buku Teks
Garcia, Ofelia, author
Wiley-Blackwell , 2009
Buku Teks
Bagley, Constance E., author
South Western Cengage Learning, 2013
Buku Teks