Ho, Yin Wong, author
Business Expert Press, 2011
Buku Teks
Mullins, John W., author
McGraw-Hill , 2013
Buku Teks
Malhotra, Naresh K.
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Buku Teks
Carson, David, author
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Buku Teks
Brown, F.E.
Addison Wesley c. , 1980
Buku Teks