APA-referens (7:e uppl.)

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.

Chicago-referens (17:e uppl.)

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.

MLA-referens (9:e uppl.)

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.