SHUKUROV, A. S. On the Number of Non-Real Eigenvalues of the Sturm-Liouville Problem. Eurasian Mathematical Journal, [S. l.], v. 8, n. 3, p. 77–84, 2017. Disponível em: https://emj.enu.kz/index.php/main/article/view/673. Acesso em: 18 sep. 2025.