Kirn, Elaine
Interactions I. a communicative grammar / Elaine Kirn, Darcy Jack
McGraw-Hill, 1990
Buku Teks
Warner, Patricia K.
Interactions II : a communicative grammar
MacGraw-Hill, 1990
Buku Teks
Simanjuntak, Herpinus
German Grammar and Conversation Handbook
Kesaint Blanc, 2017
Buku Teks
Modern German Grammar workbook / by Bill Dodd...[et.al]
Routledge, 1996
Buku Teks
Azar, Betty Schrampfer, 1941-
Understanding and using English grammar
Prentice Hall Regents, 1989
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