Mennes, L.B.M., author
North-Holland Publishing, 1969
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Sekretariat Negara, 1998
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Gilley, Jerry W., author
American Society for Training & Development, 1992
eBooks
Gilley, Jerry W., author
[American Society for Training and Development Press, American Society for Training and Development Press], 1998
eBooks
Ohlin, Goran
Paris OECD Development Centre 1967,
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