LINDSTRÖM, M.; SCHÜCHTERMANN, G. Composition of operator ideals. MATHEMATICA SCANDINAVICA, [S. l.], v. 84, n. 2, p. 284–296, 1999. DOI: 10.7146/math.scand.a-13880. Disponível em: https://www.mscand.dk/article/view/13880. Acesso em: 2 may. 2024.