Existence Results for the Positive Solutions of a Fourth Order Nonlinear Equations on the Heisenberg Group. Journal of Partial Differential Equations, [S. l.], v. 13, n. 2, p. 123–132, 2000. Disponível em: https://global-sci.com/index.php/jpde/article/view/3937. Acesso em: 5 dec. 2025.