BATES, Teresa; PASK, David. $C^*$-algebras of labelled graphs II - simplicity results. Mathematica Scandinavica, Berkeley, CA, United States, v. 104, n. 2, p. 249–274, 2009. DOI: 10.7146/math.scand.a-15097. Disponível em: https://journals.msp.org/mscand/article/view/600. Acesso em: 24 jul. 2026.