Journal of the Mathematical Society of Japan · 1967 · 26 citations · 3 references
Natural SciencesMathematicsDynamical SystemsEigenvalue ProblemsOperator TheoryPerturbation MethodsPerturbation TheorySingular Perturbation TheorySpectral TheoryNon-degenerate Perturbation TheoryNon-self-adjoint OperatorsPerturbation Theory Of OperatorsSelf-adjoint Eigenvalue ProblemsSelf-adjoint Operators
3
On the perturbation of continuous spectra
Kurt Friedrichs · Communications on Pure and Applied Mathematics · 1948 · 540 citations
Wave operators and similarity for some non-selfadjoint operators
Tosio Kato · Mathematische Annalen · 1966 · 474 citations
Some non‐selfadjoint operators
J. T. Schwartz · Communications on Pure and Applied Mathematics · 1960 · 162 citations