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John Wiley & Sons, 1989
Buku Teks
edited by Samuel Rapport and Helen Wright
New American Library, 1962
Buku Teks
Holmes, D.C.
Macmillan, 1960
Buku Teks
Rothery, David A.
Teach Yourself, 2017
Buku Teks
Wilson, Gilbert
George Allen, 1982
Buku Teks