Weyl Type Theorems for Left and Right Polaroid Operators

Pseudo-Inverses in Associative Rings and Semigroups

Michael P. Drazin · American Mathematical Monthly · 1958 · 698 citations

Natural Sciences, Mathematics, Algebra +10

On a class of quasi-Fredholm operators

Mohammed Berkani · Integral Equations and Operator Theory · 1999 · 187 citations

Natural Sciences, Architectural Representation, Representation Theory +6

On semi B-Fredholm operators

Mohammed Berkani, M. Sarih · Glasgow Mathematical Journal · 2001 · 161 citations · Full text

Natural Sciences, Mathematics, Dynamical Systems +10

Uniform ascent and descent of bounded operators

Sandy Grabiner · Journal of the Mathematical Society of Japan · 1982 · 147 citations · Full text

Natural Sciences, Mathematics, Circuit Theory +9

Index of B-Fredholm operators and generalization of a Weyl theorem

Mohammed Berkani · Proceedings of the American Mathematical Society · 2001 · 147 citations · Full text

Natural Sciences, Computer Science, Mathematics +9