Artikel Jurnal
N.Y. Charles Scribner's Sons , 1954
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Ruffa, Stephen A., 1961- , author
American Management Association, 2008
eBooks
Wibbels, Erik, author
Cambridge University Press, 2005
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Stephan Haggard, editor; Wonhyuk Lim, editor; Euysung Kim, editor
Cambridge University Press, 2003
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