National Council of Teachers of Mathematics. (1957). Insights into modern mathematics: Twenty-third yearbook.
Chicago Style (17th ed.) CitationNational Council of Teachers of Mathematics. Insights into Modern Mathematics: Twenty-third Yearbook. Washington, 1957.
MLA (9th ed.) CitationNational Council of Teachers of Mathematics. Insights into Modern Mathematics: Twenty-third Yearbook. 1957.
Warning: These citations may not always be 100% accurate.