HU, S.; LIN, H.; XUE, Y. The tracial topological rank of extensions of $C^*$-algebras. MATHEMATICA SCANDINAVICA, [S. l.], v. 94, n. 1, p. 125–147, 2004. DOI: 10.7146/math.scand.a-14433. Disponível em: https://www.mscand.dk/article/view/14433. Acesso em: 29 apr. 2024.