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2. On pseudomonotone elliptic operators with functional dependence on unbounded domains
3. J. L. Lions, Quelques methodes de resolution des probl`emes aux limites non lineaires (in French), Dunod, Gauthier-Villars, Paris, 1969.
4. Chapter 6 Application of Monotone Type Operators to Parabolic and Functional Parabolic PDE's
5. Multiple solutions of nonlinear partial functional differential equations and systems