ARLINSKY, Yu. M.; MOGILEVSKII, V. I. Commuting extensions of operators. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 45, n. 6, p. 744–752, 1993. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5863. Acesso em: 11 apr. 2025.