BIŞGIN, M. C.; SÖNMEZ, A. Compactness of quadruple band matrix operator and geometric properties. Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica, [S. l.], v. 21, p. 17–32, 2022. Disponível em: https://studmath.uken.krakow.pl/article/view/9488. Acesso em: 16 may. 2024.