Mattel, Bruce, author
John Wiley & Sons, 2008
Buku Teks
Rowe, Alan J., author
Macmillan, 1992
Buku Teks
Flynn, Nancy, author
American Management Association, 2006
eBooks
Starr, Martin K., author
Prentice-Hall, 1989
Buku Teks
Shattock, Michael, author
Open University Press, 2005
Buku Teks