Ewald, Helen Rothschild
Prentice Hall International, 1997
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Quible, Zone K.
Prentice Hall International,inc, 1996
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Krizan, A. C. (Buddy), author
Thomson, 2008
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Ewald, Helen Rothschild, author
Prentice-Hall International, 1997
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Roebuck, Deborah Britt, author
Business Expert Press, 2012
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