Harrison, M. (2012). Cambridge English: Proficiency practice tests : with key : five tests for Cambridge English : proficiency: Mark Harrison. Oxford University Press.
Chicago-viite (17. p.)Harrison, Mark. Cambridge English: Proficiency Practice Tests : With Key : Five Tests for Cambridge English : Proficiency: Mark Harrison. Oxford: Oxford University Press, 2012.
MLA-viite (8. p.)Harrison, Mark. Cambridge English: Proficiency Practice Tests : With Key : Five Tests for Cambridge English : Proficiency: Mark Harrison. Oxford University Press, 2012.
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