In this paper, we prove that if a Banach space X admits a Lipschitz β-smooth bump function, then any continuous convex function on a convex open subset Ω of X is β-differentiable in a dense GδG_\delta subset of Ω.

Contact details are reproduced from the original publication and may be historical.

Yongxin Li

Nankai Institute of Mathematics, Tianjin, 300071, People’s Republic of China

Shuzhong Shi

Nankai Institute of Mathematics, Tianjin, 300071, People’s Republic of China

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Y. Li, S. Shi. “Differentiability of Convex Functions on a Banach Space with Smooth Bump Function.” Journal of Convex Analysis 1 (1994), No. 1, 47–60. https://doi.org/10.68381/jca01003