Alawiyah A, Budi Waluya S, Priyono Budi Prasetyo A. Didactical Situations of Students’ Mathematical Reasoning Based on the Learning Obstacle on Quadrilateral Areas. UJMER [Internet]. 25Sep.2018 [cited 26Apr.2024];7(1):196-03. Available from: https://journal.unnes.ac.id/sju/ujmer/article/view/25533