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Foreign Languages Publishing, [date of publication not identified]
Buku Teks SO
Wallwork, Adrian
Springer, 2010
Buku Teks SO
Emmerson, Paul
Cambridge University Press, 2005
Buku Teks SO
Moran, Robert T.
Gulf, 1991
Buku Teks
Cellich, Claude
Business Expert Press, 2012
Buku Teks