Clayton, H. W., & Straker, D. N. (1965). Natural approach to mathematics. 5v.
Chicago Edition CitationClayton, H. W., and D. N. Straker. Natural Approach to Mathematics. 5v. 1965.
MLA Edition CitationClayton, H. W., and D. N. Straker. Natural Approach to Mathematics. 5v. 1965.
Warning: These citations may not always be 100% accurate.