1. The open ended approach: A new proposal for teaching mathematics;Becker,1997
2. The art of problem posing;Brown,1993
3. Cai, J. (1995). A cognitive analysis of U.S. and Chinese students’ mathematical performance on tasks involving computation, simple problem solving, and complex problem solving (Journal for Research in Mathematics Education Monograph Series No. 7). Reston, VA: National Council of Teachers of Mathematics.
4. Exploring mathematical exploration: How two college students formulated and solved their own mathematical problems?;Cai;Focus on Learning Problems in Mathematics,2005
5. Algorithms in solving non-routine problems;Cai,1998