O'Dell F. Felicity & Black M. Michael. (2015). Advanced Trainer. Six Practice Tests with Answers (2-nd ed.). Cambridge, Cambridge University Press, 2015.
Chicago-viite (17. p.)O'Dell F. Felicity ja Black M. Michael. Advanced Trainer. Six Practice Tests with Answers. 2-nd ed. Cambridge, Cambridge University Press, 2015, 2015.
MLA-viite (9. p.)O'Dell F. Felicity ja Black M. Michael. Advanced Trainer. Six Practice Tests with Answers. 2-nd ed. Cambridge, Cambridge University Press, 2015, 2015.
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