Kim, Yeong Rae
Geullobed bijeunisen sageon = English--Korean dictionary of global business
Bubyoungsa, 2006
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English workshop
New York : Holt, Rinehart and Winston, 1995,
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Holschuh, Louis W.
The functions of the English grammer/Louis W. Holscchuh
New York St. Martin's Press 1991,
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English grammatical structure : a general syllabus for teachers / L.G. Alexander...[et al.]
Longman Group UK Limited , 1975
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Klatt, Edmund
Langenscheidts Schulworterbuch English-Deutch; Deutsch English
Berlin Langenscheidt KG. Verlag buchhandlung 1961
 Buku Referensi