Freudenthal, H. (1978). Change in mathematics education sicne the late 1950's: Ideas and realisation. D. Reidel.
Chicago-viite (17. p.)Freudenthal, Hans. Change in Mathematics Education Sicne the Late 1950's: Ideas and Realisation. Dordrecht: D. Reidel, 1978.
MLA-viite (9. p.)Freudenthal, Hans. Change in Mathematics Education Sicne the Late 1950's: Ideas and Realisation. D. Reidel, 1978.
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