Hypoellipticity of Nonlinear Second Order Partial Differential Equations. Journal of Partial Differential Equations, [S. l.], v. 1, n. 1, p. 85–95, 2018. Disponível em: https://www.global-sci.com/index.php/jpde/article/view/3596. Acesso em: 5 dec. 2025.