Variational methods for non-differentiable functionals and their applications to partial differential equations

Dual variational methods in critical point theory and applications

Antonio Ambrosetti, Paul H. Rabinowitz · Journal of Functional Analysis · 1973 · 4.4K citations

Natural Sciences, Mathematics, Physics +14

A New Approach to Lagrange Multipliers

Frank H. Clarke · Mathematics of Operations Research · 1976 · 502 citations

Natural Sciences, Mathematics, Algorithms +11

Critical point theorems for indefinite functionals

Vieri Benci, Paul H. Rabinowitz · Inventiones mathematicae · 1979 · 428 citations

Natural Sciences, Materials Science, Critical Theory +7

A Variant of the Lusternik-Schnirelman Theory

David Clark · Indiana University Mathematics Journal · 1972 · 313 citations

Natural Sciences, Mathematics, Mathematical Physics +4

The obstacle problem and partial differential equations with discontinuous nonlinearities

Kai‐Wei Chang · Communications on Pure and Applied Mathematics · 1980 · 161 citations

Natural Sciences, Mathematics, Mechanical Engineering +16