Swan, Michael
The new cambridge english course 3
Cambridge University Press, 1992
 Buku Teks SO
Allsop, Jake
English for Cambridge first certificate: a new course
Cassell, 1981
 Buku Teks SO
Swan, Michael
The new Cambridge English course. Student 4, Upper-intermediate
Cambridge University Press, 1993
 Buku Teks SO
Crystal, David, 1941-
The Cambridge encyclopedia of the English language
Cambridge University Press, 1995
 Buku Referensi
Cambridge international dictionary of english
editor in chief Paul Procter
Cambridge University Press, 1995
 Buku Referensi