LE, V. K. On second order elliptic equations and variational inequalities with anisotropic principal operators. Topological Methods in Nonlinear Analysis, [S. l.], v. 44, n. 1, p. 41–72, 2016. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2014.035. Acesso em: 22 jul. 2024.