ZALMAI G.J. Proper efficiency conditions and duality models for nonsmooth multiobjective fractional programming problems with operator constraints, Part II: Applications. Utilitas Mathematica , [S. l.], v. 51, 1997. Disponível em: https://utilitasmathematica.com/index.php/Index/article/view/68. Acesso em: 8 may. 2026.