Bate, Paul, author
John Wiley & Sons, 1981
Buku Teks
Smith, Cyril, author
McGraw-Hill, 1977
Buku Teks
ASTD Research Study
American Society for Training & Development, 2011
eBooks
Lykins, Lorrie, author
American Society for Training & Development, 2011
eBooks
edited by Ray Wood
CCH Australia, 1978
Buku Teks