Gilmore, Thomas North, author
Jossey Bass, 1988
Buku Teks
Rastafarian, author
2017
UI - Skripsi (Membership)
Harvey, Thomas R.
Allyn and Bacon, 1990
Buku Teks
Carr, Patricia A.
American Society for Training & Development, 2006
eBooks
Harvard Business School
Harvard Business Review Press, 2011
Buku Teks