RADZIEVSKY , G. V. Equivalence of almost root vectors of polynomial beams of operators . Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 44, n. 7, p. 948–970, 1992. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/8128. Acesso em: 14 apr. 2025.