“ Spectral properties for polynomial and matrix operators involving demicompactness classes : doi:10.17398/2605-5686.33.1.11”, Extr. Math., vol. 33, no. 1, p. 11–32, Jun. 2018, Accessed: Dec. 21, 2024. [Online]. Available: https://revista-em.unex.es/index.php/EM/article/view/2605-5686.33.1.11