Butler, C. H., & Wren, F. L. (1951). The teaching of secondary mathematics (2d ed.). McGraw-Hill.
Chicago Style (17th ed.) CitationButler, Charles H., and Frank Lynwood Wren. The Teaching of Secondary Mathematics. 2d ed. New York: McGraw-Hill, 1951.
MLA (9th ed.) CitationButler, Charles H., and Frank Lynwood Wren. The Teaching of Secondary Mathematics. 2d ed. McGraw-Hill, 1951.
Warning: These citations may not always be 100% accurate.