Demircioğlu H, Hatip K. Examining Students’ Proof Writing and Justification Skills in the Context of Sum of Measures of Polygons’ Interior Angles. IEJEE [Internet]. 2023Oct.1 [cited 2025Apr.4];16(1):17-30. Available from: https://iejee.com/index.php/IEJEE/article/view/1997