1. Ricceri, B., Un Théorème d'Existence pour les Inéquations Variationnelles, Comptes Rendus de l'Académie des Sciences, Paris, Série I, Vol. 301, pp. 885?888, 1985.
2. Hartman, P., andStampacchia, G.,On Some Nonlinear Elliptic Differential Equations, Acta Mathematica, Vol. 115, pp. 271?310, 1966.
3. Harker, P. T., andPang, J. S.,Finite-Dimensional Variational Inequality and Nonlinear Complementarity Problems: A Survey of Theory, Algorithms, and Applications, Mathematical Programming, Vol. 48, pp. 161?220, 1990.
4. Aubin, J. P., andFrankowska, H.,Set-Valued Analysis, Birkhäuser, Basel, Switzerland, 1990.
5. Marano, S. A.,Controllability of Partial Differential Inclusions Depending on a Parameter and Distributed-Parameter Control Processes, Le Matematiche (to appear).