edited by Nicholas Benwell
Halsted Press, 1975
Buku Teks SO
Stanley, Julian C.
Prentice-Hall, 1972
Buku Teks
DeTuncq, Toni
American Society for Training & Development, 2012
eBooks
Nunnally, Jum C.
McGraw-Hill, 1972
Buku Teks
Franklin, Maren
American Society for Training and Development Press, 2005
eBooks