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Buku Teks
Coe, Rodney M.
McGraw-Hill, 1970
Buku Teks
edited by Jonathan Gabe, Michael Calnan and Michael Bury
Routledge , 1991
Buku Teks
Macmillan Company of Australia, 1989
Buku Teks
Maykovich, Minako K.
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Buku Teks