Palmer, Ian R., author
McGraw-Hill, 2006
Buku Teks
Berko, Roy M, author
Houghton Miffiln, 2001
Buku Teks
Kissler, Gary D., author
Addison-Wesley, 1991
Buku Referensi
Prentice-Hall, 2000
Buku Teks
Cowan, Stella Louise, author
[American Society for Training & Development Press, American Society for Training & Development Press], 2001
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