Kenny, Philip H.
Butterworth, 1994
Buku Teks
by Malcolm Hardy ... [and others]
Weidenfeld and Nicolson, 1990
Buku Teks SO
edited by Kevin McConway and Basiro Davey
Open University Press, 2003
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Nightingale, Virginia
Routledge, 1996
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Abdelrahman Tareq Sadeq Elsharqawy
Graduate School of Language and Culture, Osaka University, 2019
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