Frank, M. (1972). Modern english: Exercises for non-native speakers. Prentice-Hall.
Chicago-viite (17. p.)Frank, Marcella. Modern English: Exercises for Non-native Speakers. Englewood Cliffs: Prentice-Hall, 1972.
MLA-viite (9. p.)Frank, Marcella. Modern English: Exercises for Non-native Speakers. Prentice-Hall, 1972.
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