GARRONI, M. G.; SOLONNIKOV, V. A.; VIVALDI, M. A. On the oblique derivative problem in an infinite angle. Topological Methods in Nonlinear Analysis, [S. l.], v. 7, n. 2, p. 299–325, 1996. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.1996.014. Acesso em: 22 lip. 2024.