Li, Chong et Ni, Ren Xing, On Well-posed Mutually Nearest and Mutually Furthest Point Problems in Banach Spaces, Acta mathematica Sinica. English series (Print) , 20(1), 2004, pp. 147-156
Let G be a non-empty closed (resp. bounded closed) boundedly relatively weakly compact subset in a strictly convex Kadec Banach space X. Let K(X) denote the space of all non-empty compact convex subsets of X endowed with the Hausdorff distance. Moreover, let KG(X) denote the closure of the set {AK(X):AG=}. We prove that the set of all AKG(X)(resp.AK(X)) , such that the minimization (resp. maximization) problem min(A,G) (resp. max(A,G)) is well posed, contains a dense G -subset of KG(X)(resp.K(X)), thus extending the recent results due to Blasi, Myjak and Papini and Li.