BHATI, D.; SINGH, P. Multi-objective nonlinear sum of fractional optimization problems with non-convex constraints using duality based branch and bound algorithm. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 69, n. 11, p. 1455–1471, 2017. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1795. Acesso em: 5 dec. 2025.