Artikel Jurnal
Major, Ralph H., author
W.B. Saunders, 1958
Buku Teks
Major, Ralph H., author
W.B. Saunders, 1964
Buku Referensi
Murrell, Kenneth L., author
[American Society for Training and Development Press;American Society for Training and Development Press, American Society for Training and Development Press], 1997
eBooks
edited by Jamie H. Von Roenn, Judith A. Paice, Michael E. Preodor
Lange Medical Books/McGraw-Hill, 2006
Buku Teks