Elbir, Dilara, and Zeynep Medine Özmen. “Investigation of Patterns in Secondary School Mathematics Textbooks in the Context of Transition from Arithmetic to Algebra”. Turkish Journal of Mathematics Education 4, no. 2 (August 31, 2023): 1–26. Accessed May 21, 2024. https://tujme.org/index.php/tujme/article/view/80.