LAITH K. SHAAKIR; SAAD S. MARAI. quasi-normal Operator of order n. Tikrit Journal of Pure Science, [S. l.], v. 20, n. 4, p. 167–169, 2023. DOI: 10.25130/tjps.v20i4.1231. Disponível em: http://tjps.tu.edu.iq/index.php/tjps/article/view/1231. Acesso em: 13 nov. 2024.