Variational and Non-variational Methods in Nonlinear Analysis... - 9781441952486

Benci - Variational and Topological Methods in the Study of Nonlinear - X555z

Motreanu - Topological and Variational Methods with Applications to No - X555z

Variational Methods in Nonlinear Field Equations: Solitary... - Benci, Vieri

Fliess - Algebraic and Geometric Methods in Nonlinear Control Theory - - X555z

Rektorys - Variational Methods in Mathematics Science and Engineering - X555z

Costea - Variational and Monotonicity Methods in Nonsmooth Analysis - - X555z