HANCHE-OLSEN, H. Split faces and ideal structure of operator algebras. MATHEMATICA SCANDINAVICA, [S. l.], v. 48, p. 137–144, 1981. DOI: 10.7146/math.scand.a-11906. Disponível em: https://www.mscand.dk/article/view/11906. Acesso em: 14 apr. 2025.