HEINONEN, Juha; KILPELÄINEN, Tero. Polar sets for supersolutions of degenerate elliptic equations. MATHEMATICA SCANDINAVICA, [S. l.], v. 63, p. 136–150, 1988. DOI: 10.7146/math.scand.a-12229. Disponível em: https://www.mscand.dk/article/view/12229. Acesso em: 5 dec. 2025.