KARAEV, M. T.; ISKENDEROV, N. Sh. Berezin number of operators and related questions. Methods of Functional Analysis and Topology, [S. l.], v. 19, n. 1, p. 68–72, 2013. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/536. Acesso em: 16 dec. 2025.