A Robust Finite Element Method for a 3-D Elliptic Singular Perturbation Problem. Journal of Computational Mathematics, [S. l.], v. 25, n. 6, p. 631–644, 2021. Disponível em: https://global-sci.com/index.php/JCM/article/view/11854. Acesso em: 5 dec. 2025.