Naylor, H., & Murphy, R. (2007). Essential Grammar in use suplementary exercises, with answers (2a. ed.). Cambridge University Press.
Chicago Style (17th ed.) ZitazioaNaylor, Helen, eta Raymond Murphy. Essential Grammar in Use Suplementary Exercises, with Answers. 2a. ed. Cambridge University Press, 2007.
MLA (9th ed.) ZitazioaNaylor, Helen, eta Raymond Murphy. Essential Grammar in Use Suplementary Exercises, with Answers. 2a. ed. Cambridge University Press, 2007.
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