Tuleja, Tad
Facts On File Publications, 1985
Buku Teks
Warner, W. Lloyd, author
Harper & Brothers , 1955
Buku Teks
Phillips, Jack J., author
American Society for Training & Development, 2008
eBooks
Liautaud, Bernard, 1962-, author
McGraw-Hill, 2000
Buku Teks
Hatten, Timothy S., author
Prentice-Hall, 1997
Buku Referensi