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On Hopf's Lemma and the Strong Maximum Principle

S. Bertone·A. Cellina·E. M. Marchini
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Abstract

In this paper we consider Hopf's Lemma and the Strong Maximum Principle for supersolutions to a class of non elliptic equations. In particular we prove a sufficient condition for the validity of Hopf's Lemma and of the Strong Maximum Principle and we give a condition which is at once necessary for the validity of Hopf's Lemma and sufficient for the validity of the Strong Maximum Principle.

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S. Bertone, A. Cellina, E. M. Marchini. 2005-01-28. On Hopf's Lemma and the Strong Maximum Principle. https://arxiv.org/abs/math/0501503

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