National Council of Teachers of Mathematics, Krulik, S., & Reys, R. E. (1980). Problem solving in school mathematics: 1980 NCTM yearbook. NCTM.
Chicago Style (17th ed.) CitationNational Council of Teachers of Mathematics, Stephen Krulik, and Robert E. Reys. Problem Solving in School Mathematics: 1980 NCTM Yearbook. Reston, VA: NCTM, 1980.
MLA (9th ed.) CitationNational Council of Teachers of Mathematics, et al. Problem Solving in School Mathematics: 1980 NCTM Yearbook. NCTM, 1980.
Warning: These citations may not always be 100% accurate.