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On Lipschitz and d.c. surfaces of finite codimension in a Banach space

Luděk Zajíček
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Abstract

Properties of Lipschitz and d.c. surfaces of finite codimension in a Banach space, and properties of generated $\sigma$-ideals are studied. These $\sigma$-ideals naturally appear in the differentiation theory and in the abstract approximation theory. Using these properties, we improve an unpublished result of M. Heisler which gives an alternative proof of a result of D. Preiss on singular points of convex functions.

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Luděk Zajíček. 2007-01-31. On Lipschitz and d.c. surfaces of finite codimension in a Banach space. https://arxiv.org/abs/math/0701926

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