AL-HAMDANY, entithar. The impact of the constructive John Zahrek model on the achievement of the third -grade students in mathematics and the development of their side thinking. College of Basic Education Research Journal, [S. l.], v. 18, n. 3, p. 249–276, 2022. DOI: 10.33899/berj.2022.175666. Disponível em: https://moss.uomosul.edu.iq/index.php/berj/article/view/37962. Acesso em: 26 oct. 2025.