BROWN, Robert F.; GONÇALVES, Daciberg Lima. Lift factors for the Nielsen root theory on $n$-valued maps. Topological Methods in Nonlinear Analysis, [S. l.], v. 61, n. 1, p. 269–289, 2023. DOI: 10.12775/TMNA.2022.017. Disponível em: https://apcz.umk.pl/TMNA/article/view/42812. Acesso em: 27 dec. 2025.