Extinction and Positivity for the Non-Newtonian Polytropic Filtration Equation. Journal of Partial Differential Equations, [S. l.], v. 9, n. 2, p. 169–176, 1996. Disponível em: https://gsp.tricubic.dev/jpde/article/view/3823. Acesso em: 15 mar. 2026.