Tracy, Brian
John Wiley & Sons, 2003
Buku Teks
Abrahan, Joe,author
McGraw-Hill, 2011
Buku Teks
Hedges, Kristi
[American Management Association, ], 2012
eBooks
Mattone, John
[American Management Association, ], 2013
eBooks
Betof, Edward
American Society for Training & Development, 2009
eBooks