CHARATONIK, Włodzimierz; MICHALIK, Daria. Properties of Multi-Valued Functions. Topology Proceedings, [S. l.], v. 60, p. 45–57, 2021. Disponível em: https://www.topologyproceedings.org/index.php/tp/article/view/60. Acesso em: 30 jun. 2026.