Routledge, London: Routledge, 1991
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Tanham, George K., author
Frederick A. Praeger, 1967
Buku Teks
Fall, Bernard B
Frederick A.Preager, 1966
Buku Teks
Nguyen-Vien
Foreign Language Publishing House, 1956
Buku Teks
Souter, Gerry, author
Andre Deutsch, 2015
Buku Referensi