McKay, Herbert
Oxford University Press, 1950
Buku Teks
Pincas, Anita
Macmillan Press, 1983
Buku Teks
McCarthy, Michael
Cambridge University Press, 1999
Buku Teks
Barker, D. W.
Macmillan and Co., 1953
Buku Teks
Griffin, Suzanne
BBC English, 1989
Buku Teks