MATHEMATICS, N. C. O. T. O. (1963). Enrichment Mathematics for the Grades. National Council of Teachers of Mathematics.
Chicago-viite (17. p.)MATHEMATICS, NATIONAL COUNCIL OF TEACHERS OF. Enrichment Mathematics for the Grades. National Council of Teachers of Mathematics, 1963.
MLA-viite (8. p.)MATHEMATICS, NATIONAL COUNCIL OF TEACHERS OF. Enrichment Mathematics for the Grades. National Council of Teachers of Mathematics, 1963.
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