A twist condition and periodic solutions of Hamiltonian systems

Periodic solutions of hamiltonian systems

Paul H. Rabinowitz · Communications on Pure and Applied Mathematics · 1978 · 735 citations

Natural Sciences, Mathematics, Physics +13

Morse‐type index theory for flows and periodic solutions for Hamiltonian Equations

Charles C. Conley, Eduard Zehnder · Communications on Pure and Applied Mathematics · 1984 · 466 citations

Natural Sciences, Mathematics, Differential Equations +13

Generalized cohomological index theories for Lie group actions with an application to bifurcation questions for Hamiltonian systems

Edward Fadell, Paul H. Rabinowitz · Inventiones mathematicae · 1978 · 390 citations

Natural Sciences, Mathematics, Physics +17

Nontrivial solutions for a class of nonresonance problems and applications to nonlinear differential equations

Herbert Amann, Edward J. Zehnder · French digital mathematics library (Numdam) · 1980 · 314 citations

Natural Sciences, Mathematics, Computational Electromagnetics +13

Saddle points and multiple solutions of differential equations

Herbert Amann · Mathematische Zeitschrift · 1979 · 200 citations

Natural Sciences, Mathematics, Differential Equations +14