BRENKEN, B. Topological quivers as multiplicity free relations. MATHEMATICA SCANDINAVICA, [S. l.], v. 106, n. 2, p. 217–242, 2010. DOI: 10.7146/math.scand.a-15134. Disponível em: https://www.mscand.dk/article/view/15134. Acesso em: 7 apr. 2025.