Begle, E. G. (1979). Critical variables in mathematics education: Findings from a survey of the empirical literature. Mathematical Association of America : National Council of Teachers of Mathematics.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Begle, Edward Griffith. Critical Variables in Mathematics Education: Findings from a Survey of the Empirical Literature. Washington, D.C: Mathematical Association of America : National Council of Teachers of Mathematics, 1979.
Trích dẫn kiểu MLA (xuất bản lần thứ 9)Begle, Edward Griffith. Critical Variables in Mathematics Education: Findings from a Survey of the Empirical Literature. Mathematical Association of America : National Council of Teachers of Mathematics, 1979.
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