ALEXANDER, L. (1986). Question and answer graded oral comprehension exercises. Kanisius.
Chicago-viite (17. p.)ALEXANDER, L.G. Question and Answer Graded Oral Comprehension Exercises. Kanisius, 1986.
MLA-viite (8. p.)ALEXANDER, L.G. Question and Answer Graded Oral Comprehension Exercises. Kanisius, 1986.
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