1. Aubin, J. -P. and Ekeland, I.:Applied Nonlinear Analysis, Wiley, New York, 1984.
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4. Borwein, J. M.: Adjoint process duality,Math. Oper. Res. 8 (1983), 403?434.
5. Crouzeix, J. -P.: Continuit� des applications lin�aires multivoques,PAIRO 7 (1973), R-1, 62?67.