Gabdullin, R., Kozhabaev, K. and Kostangeldinova, A. (2018) “Organization of educational and developmental training of school students at mathematics lessons”, Opción, 34(85), pp. 605-631. Available at: https://produccioncientificaluz.org/index.php/opcion/article/view/23741 (Accessed: 5December2025).