1. Fréchet differentiability of convex functions;Asplund;Acta Math.,1968
2. Boundedly Krein-compact Banach spaces;Asplund,1969
3. Gradients of convex functions;Asplund;Trans. Amer. Math. Soc.,1969
4. The support functionals of a convex set;Bishop,1963
5. J. Collier and M. Edelstein, On strongly exposed points and Fréchet differentiability,