MUHLY, P. S.; WILLIAMS, D. P. Continous trace groupoid $C^*$-algebras. MATHEMATICA SCANDINAVICA, [S. l.], v. 66, p. 231–241, 1990. DOI: 10.7146/math.scand.a-12307. Disponível em: https://www.mscand.dk/article/view/12307. Acesso em: 3 may. 2024.