Regularity for $p$-Harmonic Functions in the Grušin Plane. Journal of Mathematical Study, [S. l.], v. 56, n. 3, p. 219–278, 2023. DOI: 10.4208/jms.v56n3.23.01. Disponível em: https://global-sci.com/index.php/jms/article/view/13446. Acesso em: 6 dec. 2025.