ARNAL-PALACIáN, Mónica; BEGUé, Nuria; BLANCO, Cristina. The impact of sending letters in improving teaching-learning process of natural number of pre-service teachers. Journal of Honai Math, [S. l.], v. 5, n. 1, p. 61–74, 2022. DOI: 10.30862/jhm.v5i1.240. Disponível em: https://journalfkipunipa.org/index.php/jhm/article/view/240. Acesso em: 11 oct. 2026.