Muchdis
Balai Pustaka, 1950
Buku Teks
Dilenschneider, Robert L.
American Management Association, 2010
eBooks
Goldsmith, Marshall
American Management Association, 2010
eBooks
Crilly, William M.
American Management Association;, 2010
eBooks
edited by Paul C. Dinsmore, Jeannette Cabanis-Brewin
American Management Association, 2006
eBooks