Ebert, Ronald J.
Business essentials
Prentice-Hall, 2003
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Ebert, Ronald J.
Business essentials
Pearson, 2015
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Anderson, W.M. (Wendy M.)
English grammar essentials for dummies
Wiley Publishing , 2013
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Smiith, Jeremy J.
Essentials of early english
Routledge, 2005
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Anderson, W.M. (Wendy M.)
English grammar essentials for dummies
Wiley Publishing Australia Pty Ltd, 2013
 Buku Teks