Boyd, Susan
American Society for Training and Development Press, 2005
eBooks
Fan, Hung
Jones And Bartlett Publishers, 2003
Buku Teks
Donatelle, Rebecca J.
Allyn and Bacon , 1997
Buku Teks
Macionis, John J.
Prentice-Hall, 2000
Buku Teks
Chandler, Daniel
Routledge, 2002
Buku Teks