Extending mathematics understanding - Osborn, Roger; DeVault, M. Vere. (Columbus, Ohio : C. E. Merrill Books, 1961)
Earlier ed. copyright 1960 under the titles Toward improved understanding of mathematics, part I and Toward improved understanding of mathematics, part II, by M. V. DeVault, published in 1960.
Revised in 1969, published separately in two volumes under the titles Understanding the number system and Extending understandings of mathematics.
Bibliography: p. 264-271.
Keywords: Mathematics -- Study and teaching (Elementary)