يونس محمود س. The Effect of Instructional – Training Program in gaining Same Conservation Concepts for Primary School Pupils Delayed in their Attainment. College of Basic Education Research Journal, [S. l.], v. 3, n. 3, p. 1–39, 2007. Disponível em: https://stats.uomosul.edu.iq/index.php/berj/article/view/39819. Acesso em: 26 oct. 2025.