MURATBEKOV, M.B.; IGISINOV, S.Zh.; MUSILIMOV, B.M.; MAKULBEKOVA, R.R. On the spectral properties of a class of high-order differential operators with operator coefficients. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 98, n. 2, p. 110–124, 2020. DOI: 10.31489/2020m2/110-124. Disponível em: https://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/346. Acesso em: 4 sep. 2025.