$P_1$-Nonconforming Quadrilateral Finite Volume Element Method and Its Cascadic Multigrid Algorithm for Elliptic Problems. Journal of Computational Mathematics, [S. l.], v. 24, n. 1, p. 59–80, 2018. Disponível em: https://global-sci.com/index.php/JCM/article/view/11745. Acesso em: 5 dec. 2025.