LIVINSKII, V. O. Essential normality of some classes of operators in tensor products of Hilbert spaces. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 46, n. 7, p. 878–885, 1994. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5679. Acesso em: 11 apr. 2025.