ISAC, G.; COJOCARU, M. G. Functions without exceptional family of elements and the solvability of variational inequalities on unbounded sets. Topological Methods in Nonlinear Analysis, [S. l.], v. 20, n. 2, p. 375–391, 2002. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2002.041. Acesso em: 22 jul. 2024.