Lower Bounds of Dirichlet Eigenvalues for General Grushin Type Bi-Subelliptic Operators. Analysis in Theory and Applications, [S. l.], v. 35, n. 1, p. 66–84, 2022. DOI: 10.4208/ata.OA-0002. Disponível em: https://global-sci.com/index.php/ata/article/view/8163. Acesso em: 5 dec. 2025.