References
- Cross R. Multivalued theorem for the product of linear relations. Linear Algebra and its Applications. 1998;277:127–134.
- Grabiner S. Ascent, descent and compact perturbations. Proc Am Math Soc. 1978;71:79–80.
- Rakocevic V. Semi-Fredholm operators with finite ascent or descent and perturbations. Proc Am Math Soc. 1995;123:3823–3825.
- Rakocevic V. Semi-Browder operators and perturbations. Stud Math. 1997;122:131–137.
- Caradus SR, Pfaffenberger WE, Yood B. Calkin algebras and algebras of operators on Banach spaces. New York (NY): Marcel Dekker; 1974.
- Fakhfakh F, Mnif M. Perturbation of semi-Browder operators and stability of Browder’s essential defect and approximate point spectrum. J Math Anal Appl. 2008;347:235–242.
- Fakhfakh F, Mnif M. Browder and semi-Browder operators and perturbation function. J Extracta Math. 2009;24:219–241.
- Rakocevic V. Approximate point spectrum and commuting compact perturbations. Glasgow Math J. 1986;28:193–198.
- Fakhfakh F, Mnif M. Perturbation theory of lower semi-Browder multivalued linear operators. Publ Math Debrecen. 2011;78:595–606.
- Alvarez T, Fakhfakh F, Mnif M. Coperturbation function and lower semi-Browder multivalued linear operators. Linear Multilinear Algebra. 2013;61:494–516.
- Wilcox D. Multivalued semi-Fredholm operators in normed linear spaces, [doctoral thesis]. University of Cape Town; 2002.
- Sandovici A. H. d. Snoo, H. Winkler, Ascent, descent, nullity, defect, and related notions for linear relations in linear spaces. Linear Algebra Appl. 2007;423:456–497.
- Lambek J. Lectures on rings and modules. Massachusetts-Toronto-London, Blaisdell: Waltham; 1966.
- Alvarez T. On regular linear relations. Acta Math Sinica English Ser. 2012;28:183–194.
- Chafai E, Mnif M. Descent and essential descent spectrum of linear relations. Extracta Math. 2014;29:117–139.
- Alvarez T, Wilcox D. Perturbation theory of multivalued Atkinson operators in normed spaces. Bull Aust Math Soc. 2007;76:195–204.
- Chafai E. Ascent, Descent and some perturbation results for linear relations, [doctoral thesis]. University of Sfax-Tunisie; 2013.
- Chafai E, Mnif M. Spectral mapping theorem for ascent, essential ascent, descent and essential descent spectrum of linear relations. Acta Math Sci. 2014;34:1212–1224.
- Tylli H-O. On the asymptotic behaviour of some quantities related to semi-Fredholm operators. J London Math Soc. 1985;31:340–348.
- Chamkha Y, Mnif M. Browder spectra of upper triangular matrix linear relations. Publ Math Debrecen. 2013;82:569–590.
- Goldman MA, Kračkovskii SN. Behaviour of the space of zero elements with finite-dimensional salient on the Riesz kernel under perturbations of the operator. Dokl Akad Nauk SSSR. 1975;221:532–534; Russian, English transl. Soviet Math Dokl. 1975;16:370--373.