University of Cambridge. (2012). Cambridge First Certificate in English 4 with answers: Official examination papers from University of Cambridge ESOL examinations. New York: Cambridge university Press.
Chicago-tyylinen lähdeviittausUniversity of Cambridge. Cambridge First Certificate in English 4 With Answers: Official Examination Papers From University of Cambridge ESOL Examinations. New York: Cambridge university Press, 2012.
MLA-viiteUniversity of Cambridge. Cambridge First Certificate in English 4 With Answers: Official Examination Papers From University of Cambridge ESOL Examinations. New York: Cambridge university Press, 2012.
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