RIEDESEL, C. (1973). Guiding discovery in elementary school mathematics. Prentice Hall.
Chicago-viite (17. p.)RIEDESEL, C.Alan. Guiding Discovery in Elementary School Mathematics. Englewood cliffs: Prentice Hall, 1973.
MLA-viite (9. p.)RIEDESEL, C.Alan. Guiding Discovery in Elementary School Mathematics. Prentice Hall, 1973.
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