Somervell, E. L. (1975). A rhythmic approach to mathematics. National Council of Teachers of Mathematics.
Dyfyniad Arddull ChicagoSomervell, Edith L. A Rhythmic Approach to Mathematics. [Reston, Va.]: National Council of Teachers of Mathematics, 1975.
Dyfyniad MLASomervell, Edith L. A Rhythmic Approach to Mathematics. National Council of Teachers of Mathematics, 1975.
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