Zülfiye Zeybek Şimşek. “Investigating Pre-Service Teachers’ Ability to Recognize and Classify Geometric Concepts Hierarchically”. Turkish Journal of Computer and Mathematics Education (TURCOMAT), vol. 10, no. 3, Dec. 2019, pp. 680-1, https://www.turcomat.org/index.php/turkbilmat/article/view/219.