1. Department of Mathematics, National Taiwan Normal University, Taipei, Taiwan
2. Teacher Education Center, Tainan University of Technology, Tainan, Taiwan
3. Department of Mathematics Education, National Taichung University of Education, Taichung, Taiwan
4. Graduate Institute of Mathematics and Science Education, National Chiayi University, Chiayi, Taiwan
5. Department of Education, National University of Tainan, Tainan, Taiwan