BUJUKLIEV, N. Linear cross-sections and Fredholm operators in a class groupoid $C^*$-algebras. Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 108, p. 17–21, 2021. DOI: 10.60063/gsu.fmi.108.17-21. Disponível em: https://ftl5.uni-sofia.bg/index.php/fmi/article/view/550. Acesso em: 4 dec. 2024.