edited by Janice McLean
Gale Research, 1991
Buku Referensi
Scott, Beverly, author
American Society for Training & Development, 2011
eBooks
Lowman, Rodney L., author
American Psychological Association, 2016
Buku Teks
Cope, Mick, author
Financial Times Prentice Hall, 2003
Buku Teks
Maheshwari, Shriram
The Indian Institute of Public Administration, 1972
Buku Teks