The effect of using the abacus program in developing mental math skills and logical intelligence among students of the second cycle of basic education. Sana’a University Journal of Human Sciences, [S. l.], v. 5, n. 2, 2023. DOI: 10.59628/jhs.v5i2.507. Disponível em: https://journals.su.edu.ye/index.php/jhs/article/view/507. Acesso em: 27 jun. 2026.