Houghton, F. (1911). First lessons in English for foreigners in evening schools. American Book Co.
Chicago-viite (17. p.)Houghton, Frederick. First Lessons in English for Foreigners in Evening Schools. New York, Cincinati [etc.]: American Book Co, 1911.
MLA-viite (8. p.)Houghton, Frederick. First Lessons in English for Foreigners in Evening Schools. American Book Co, 1911.
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