1. Bourke, S. and K. Stacey: 1988, ?Assessing problem solving in mathematics: Some variables related to student performance,?Australian Educational Research 15, 77?83.
2. Burton, L.: 1984,Thinking Things Through?Problem Solving in Mathematics, Blackwell, Oxford.
3. Charles, R. and F. Lester: 1982,Problem Solving: How, What and Why?, Dale Seymour, Palo Alto.
4. Cooper, M.: 1987,Cognitive and Managerial Strategies Used by Children when Deriving a Mathematical Law, private communication.
5. Cooper, M. and H. Sakane: 1986, ?Comparative experimental study of children's strategies when deriving a mathematical law?, inProceedings of the Tenth International Conference for the Psychology of Mathematics Education, PME, London, pp. 410?414.