DAVIDSON, Kenneth R. Almost commuting Hermitian matrices. Mathematica Scandinavica, Berkeley, CA, United States, v. 56, p. 222–240, 1985. DOI: 10.7146/math.scand.a-12098. Disponível em: https://journals.msp.org/mscand/article/view/1530. Acesso em: 25 jul. 2026.