Steel, Danielle, author
Corgi, 2013
Buku Teks
Stephani Zeni, author
Gramedia Pustaka Utama , 2014
Buku Teks
Emerson, Tricia, author
American Society for Training & Development, 2011
eBooks
Emerson, Tricia, author
American Society for Training & Development, 2011
eBooks
Kaplan, Burton, author
Prentice-Hall, 1995
Buku Teks