<正> 关于实或复的Banach空间 X的单位球面 S,对任一x_0∈S,都存在支撑泛函。陈道琦给出了支撑泛函唯一的一个充分条件,得到

Suppose that X is a Banach space, and S is the unity sphere, then for any point X0 S, supporting functional exists.The theorem we shall prove in this paper is as follows: Suppose that X0 S and there exist p>0, q>0, p+q=1, such thatlim sup then the supporting functional of S at point X0 is unique.