ALEXANDRU, Andrei; CIOBANU, Gabriel. Generalized Multisets: From ZF to FSM. Computing and Informatics, [S. l.], v. 34, n. 5, p. 1133–1150, 2016. Disponível em: https://www.cai.sk/ojs/index.php/cai/article/view/539. Acesso em: 30 apr. 2025.