Journal of Population, 10 ( 2) 2004 : 79-88, 2004
Artikel Jurnal
Allen, William Richard, 1924-, author
American Management Association, 1993
eBooks
Nicholson, John, author
BBC Books , 1992
Buku Teks
Odiorne, George S., author
WED International, [Date of publication not identified]
Buku Teks
Burrus, Daniel
HarperBusines, HarperBusines
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