Yen, Chong Chin, and Nor'ain Mohd Tajudin. 2015. “Assessing First Year Pre-Service Teachers’ Geometric Reasoning Ability on Two-Dimensional Shapes (1 - 12)”.
EDUCATUM Journal of Science, Mathematics and Technology 2 (1): 1-12.
https://ejournal.upsi.edu.my/index.php/EJSMT/article/view/24.