Gasinski, Leszek; Papageorgiou, Nikolaos S.
The book is as self-contained as possible and it is made more interesting by the perspectives in various sections, where the authors mention the historical background and development of the material and provide the reader with detailed explanations and updated references. [T]he book is very readable, and it can serve as a [starting] point for researchers and students [for] further investigations in the nonsmooth critical point theory as well as in its applications in mechanics, mathematical physics and engineering. - Studia Univ., Babes-Bolyai, Mathematica, Vol. XLIX, No. 3, Sept. 2004