Brue, Greg, author
Media Global Edukasi, 2005
Buku Teks
Brue, Greg, author
McGraw-Hill, 2006
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Breyfogle, Forrest W., author
John Wiley & Sons, 2001
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Manajemen Usahawan Indonesia, XXXII (01) Januari 2003: 47-49, 2003
Artikel Jurnal
Gygi, Craig, author
Wiley, 2006
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