1. J.-P. Aubin and I. Ekeland, Applied Nonlinear Analysis (J.Wiley, New York, 1984; Mir,Moscow, 1988).
2. E. Michael, “Continuous selections. I,” Ann. of Math. (2) 63(2), 361–382 (1956).
3. V. M. Tikhomirov, “A theorem on the tangent space and some of its modifications,” in Optimal Control (Izd. Moskov. Univ., Moscow, 1977), Vol. 7, pp. 22–30 [in Russian].
4. S.M. Robinson, “Regularity and stability of convex multivalued functions,” Math. Oper. Res. 1(2), 130–143 (1976).
5. E. H. Chabi and H. Zouaki, “Existence of a continuous solution of parametric nonlinear equation with constraints,” J. Convex Anal. 7(2), 413–426 (2000).