On nonlinear perturbations of the eigenvalues of a compact self-adjoint operator

Topologie et équations fonctionnelles

1934 • 757 citations

Zur Theorie der linearen und nichtlinearen Integralgleichungen

1989 • 363 citations

Lusternik-Schnirelman theory on Banach manifolds

1966 • 344 citations

Nichtlineare Integralgleichungen nebst Anwendungen

1930 • 318 citations

Störungstheorie der Spektralzerlegung

1937 • 263 citations

Vorlesungen über Himmelsmechanik

1956 • 182 citations

Zur Theorie der linearen und nichtlinearen Integralgleichungen. III. Teil

1908 • 142 citations

Branch points of solutions of equations in Banach space

1950 • 36 citations

Topologische Grundlagen der allgemeinen Eigenwerttheorie

1930 • 34 citations

Singular points of functional equations

1953 • 29 citations

A Sturm-Liouville theorem for nonlinear elliptic partial differential equations

1966 • 19 citations

Branch Points of Solutions of Equations in Banach Space

1950 • 18 citations

A STURM-LIOUVILLE THEOREM FOR NONLINEAR ELLIPTIC PARTIAL DIFFERENTIAL EQUATIONS

1965 • 13 citations

Singular Points of Functional Equations

1953 • 8 citations

Another proof of E. Hopf's ergodic lemma

1959 • 8 citations

An application of the calculus of variations in the large to the equations of nonlinear elasticity

1967 • 7 citations