PEDERSEN, N. W. The Resolutions of the Identity for Sums and Products of Commuting Spectral Operators. MATHEMATICA SCANDINAVICA, [S. l.], v. 11, p. 123–130, 1962. DOI: 10.7146/math.scand.a-10658. Disponível em: https://www.mscand.dk/article/view/10658. Acesso em: 5 may. 2024.