Kaplan, Jeffrey P.
English grammar : principles and facts
Prentice Hall International, 1995
 Buku Teks SO
Poutsma, H.
Mood and tense of the English verb / H. Poutsma
P. Noordhoff, 1922
 Buku Teks SO
English usage
edited by Tim Storrie and James Matson
Cassell , 1991
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Makkink, H.J.
An English grammar
Nijgh and Van Ditmar, 1951
 Buku Teks SO
Newby, Michael
The structure of English : a handbook of English grammar
Cambridge University Press, 1988
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