Examination papers from University of Cambridge ESOL Examinations. (2010). Cambridge Preliminary English test for schools 1 with answers. New York: Cambridge university press.
Chicago-tyylinen lähdeviittausExamination papers from University of Cambridge ESOL Examinations. Cambridge Preliminary English Test for Schools 1 With Answers. New York: Cambridge university press, 2010.
MLA-viiteExamination papers from University of Cambridge ESOL Examinations. Cambridge Preliminary English Test for Schools 1 With Answers. New York: Cambridge university press, 2010.
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