SKRYPNIK, I. I. A necessary condition for the regularity of a boundary point for degenerating parabolic equations with measurable coefficients. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 56, n. 6, p. 818–836, 2004. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3801. Acesso em: 14 apr. 2025.