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.
Lua i Stíl Chicago (17ú heag.)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.
Lua MLA (9ú heag.)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.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.