In this paper, we investigate a detailed treatment of some subsets of essential spectra of a
closed multivalued linear operator. On the following, we will establish some results on …

Perturbation theory of lower semi-Browder multivalued linear operators Page 1 Publ. Math.
Debrecen 78/3-4 (2011), 595–606 DOI: 10.5486/PMD.2011.4799 Perturbation theory of lower …

We elaborate on the deviation of the Jordan structures of two linear relations that are finite-
dimensional perturbations of each other. We compare their number of Jordan chains of …

In this paper, the notion of Drazin invertibility in the case of multivalued operators is
introduced. Many results from operator theory are covered. Applications of some obtained …

The concept of multivalued linear operators—or linear relations—is the one of the most
exciting and influential fields of research in modern mathematics. Applications of this theory …

Browder spectra of upper triangular matrix linear relations Page 1 Publ. Math. Debrecen 82/3-4
(2013), 569–590 DOI: 10.5486/PMD.2013.5300 Browder spectra of upper triangular matrix …

In the present paper, we characterize some essential spectra of a closed linear relation in
terms of certain linear relations type α α-and β β-Atkinson. This study leads us to generalize …

Let X and Y be Banach spaces. When A and B are linear relations in X and Y, respectively,
we denote by MC the linear relation in X× Y of the form M_c=\Big (A & C\0 & B) M c=(AC 0 …

Spectral Mapping Theorem for Rakocevic and Schmoeger Essential Spectra of a Multivalued
Linear Operator Page 1 Mediterr. J. Math. 12 (2015), 1019–1031 DOI 10.1007/s00009-014-0437-7 …

The classes of bounded operators on Banach spaces which satisfy a-Weyl's theorem, Weyl's
theorem and the property (w) were studied by many authors. In this paper, we introduce and …