Wichman, K.
McKay's modern German-English and English-German dictionary with rules as pronunciation
New York, David Mckay Company
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Fowler, H. W. (Henry Watson), 1858-1933
A dictionary of modern English usage
New York Oxford University Press 1965
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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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