University of Cambridge. (2005). Cambridge IELTS 4 with answers: Examination papers from University of Cambridge ESOL examinations: English for Speakers of Other Languages. New York: Cambridge university Press.
Chicago-tyylinen lähdeviittausUniversity of Cambridge. Cambridge IELTS 4 With Answers: Examination Papers From University of Cambridge ESOL Examinations: English for Speakers of Other Languages. New York: Cambridge university Press, 2005.
MLA-viiteUniversity of Cambridge. Cambridge IELTS 4 With Answers: Examination Papers From University of Cambridge ESOL Examinations: English for Speakers of Other Languages. New York: Cambridge university Press, 2005.
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