Mohd. Zariat Abdul Rani
Universiti Putra Malaysia. Faculty of Modern Languages and Communication, 2010
Artikel Jurnal
Ratnakar, Pramesh
Tiger Books International, 1996
Buku Teks SO
Utah , Salt Lake City : University of Utah Printing Service
Majalah, Jurnal, Buletin
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Scarecrow Press, 1970
Buku Teks
McKay, John P.
Houghton Mifflin , 1983
Buku Teks SO