Johnston, C. (1987). Developmental mathematics (2nd ed.). Wadsworth.
Chicago Style (17th ed.) ZitazioaJohnston, C.L. Developmental Mathematics. 2nd ed. Belmont, Calif: Wadsworth, 1987.
MLA (9th ed.) ZitazioaJohnston, C.L. Developmental Mathematics. 2nd ed. Wadsworth, 1987.
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