Crofts, F. S. (1938). Textbooks are not absolutely dead things. New York public library.
Chicago-viite (17. p.)Crofts, Frederick Sharer. Textbooks Are Not Absolutely Dead Things. New York: New York public library, 1938.
MLA-viite (9. p.)Crofts, Frederick Sharer. Textbooks Are Not Absolutely Dead Things. New York public library, 1938.
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