Copeland, R. W. (1984). How children learn mathematics: Teaching implications of Piaget's research (4th ed.). Macmillan.
Chicago-viite (17. p.)Copeland, Richard W. How Children Learn Mathematics: Teaching Implications of Piaget's Research. 4th ed. New York: Macmillan, 1984.
MLA-viite (9. p.)Copeland, Richard W. How Children Learn Mathematics: Teaching Implications of Piaget's Research. 4th ed. Macmillan, 1984.
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