OKELO, B.; JACOB, G.; KANGOGO, W. On Spectra of Symmetrized Two-Sided Multiplication Operators Implemented by Orthogonal Isometries . International Journal of Open Problems in Computer Science and Mathematics, [S. l.], v. 18, n. 4, p. 52–69, 2025. Disponível em: https://ijopcm.icsrs.uk/index.php/journal/article/view/40. Acesso em: 21 jun. 2026.