Corder, S. (1971). An intermediate english practice book: Key to the exercises. Longman.
Chicago-viite (17. p.)Corder, S.Pit. An Intermediate English Practice Book: Key to the Exercises. London: Longman, 1971.
MLA-viite (9. p.)Corder, S.Pit. An Intermediate English Practice Book: Key to the Exercises. Longman, 1971.
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