Properties of some norm related functions of unbounded linear operators

Perturbation theory for nullity, deficiency and other quantities of linear operators

Tosio Kato · Journal d Analyse Mathématique · 1958 · 520 citations

Spectral Theory, Linear Operator, Engineering +8

Unbounded Linear Operators.

U. D'Ambrosio, Seymour Goldberg · American Mathematical Monthly · 1968 · 291 citations

Spectral Theory, Infinite Dimensional Analysis, Linear Operator +4

Semigroups of operators and measures of noncompactness

Arnold Lebow, Martin Schechter · Journal of Functional Analysis · 1971 · 192 citations

Spectral Theory, Topological Semigroups, Measure Theory +3

Some continuity properties of linear transformations in normed spaces

R. W. Cross · Glasgow Mathematical Journal · 1988 · 12 citations · Full text

Principal Subspace, Principal Restriction, Infinite Dimensional Analysis +8