GUBREEV, G. M.; OLEFIR, E. I.; TARASENKO, A. A. Linear Combinations of the Volterra Dissipative Operator and Its Adjoint Operator. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 65, n. 5, p. 706–711, 2013. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2453. Acesso em: 5 dec. 2025.