Zhondo Macas AA, Cartuche Andrade MP. The numerator: manipulative material for learning basic operations in the fourth grade of General Basic Education. Revista InveCom [Internet]. 2023 Apr. 27 [cited 2026 Nov. 11];3(2):1-17. Available from: https://revistainvecom.org/index.php/invecom/article/view/591