APA
(1990). The teaching and assessing of mathematical problem solving. Virginia: National Council of Teachers of mathematics.
Chicago
1990. The teaching and assessing of mathematical problem solving. Virginia: National Council of Teachers of mathematics.
Harvard
(1990). The teaching and assessing of mathematical problem solving. Virginia: National Council of Teachers of mathematics.
MLA
The teaching and assessing of mathematical problem solving. Virginia: National Council of Teachers of mathematics. 1990.