VILKAS, E. Existence of efficient-equilibrium point of vector optimization. Lithuanian Mathematical Journal, [S. l.], v. 8, n. 1, p. 41–45, 1968. DOI: 10.15388/LMJ.1968.20179. Disponível em: https://www.journals.vu.lt/LMJ/article/view/20179.. Acesso em: 7 may. 2024.