The book is intended to be an introduction to critical point theory and its applications to differential equations. Although the related material can be found i

Many boundary value problems are equivalent to Au=O (1) where A : X --+ Y is a mapping between two Banach spaces. When the problem is variational, there exists

The book provides an introduction to minimax methods in critical point theory and shows their use in existence questions for nonlinear differential equations. A

This monograph treats the theory of Dirichlet forms from a comprehensive point of view, using "nonstandard analysis." Thus, it is close in spirit to the discret

Estimating unknown parameters based on observation data conta- ing information about the parameters is ubiquitous in diverse areas of both theory and applicatio