VISEU, F.; PIRES, A. L.; MENEZES, L.; COSTA, A. M. Semiotic Representations in The Learning of Rational Numbers by 2nd Grade Portuguese Students. International Electronic Journal of Elementary Education, [S. l.], v. 13, n. 5, p. 611–624, 2021. Disponível em: https://iejee.com/index.php/IEJEE/article/view/1453. Acesso em: 21 apr. 2025.