Cambridge IELTS with answers edition : examination papers from university of cambridge ESOL examinations
Cambridge University
Cambridge university press, 2000
 Buku Teks SO
Hopkins, Diana
Cambridge grammar for ielts with answers: self-study grammar reference and practice
Cambridge University Press, 2011
 Buku Teks
Cullen, Pauline
Cambridge vocabulary for ielts with answers : self-study vocabulary practice
Cambridge university press, 2010
 Buku Teks
Sharpe, Pamela J.
How to prepare for the TOEFL (Test Of English as a Foreign Language)
Barron's, 2001
 Buku Teks
Swan, Michael
The new cambridge english course 3
Cambridge University Press, 1992
 Buku Teks