ISTRATESCU, V. A Note on Hyponormal Operators. The Journal of the Indian Mathematical Society, [S. l.], v. 32, n. 1-2, p. 177–179, 1968. DOI: 10.18311/jims/1968/16774. Disponível em: https://www.informaticsjournals.com/index.php/jims/article/view/16774. Acesso em: 19 may. 2024.