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Digons and angular derivatives of analytic self-maps of the unit disk

Manuel D. Contreras·Santiago Díaz-Madrigal·Alexander Vasil'ev
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Abstract

We present a geometric approach to a well-known sharp inequality, due to Cowen and Pommerenke, about angular derivatives of general univalent self-maps of the unit disk.

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Manuel D. Contreras, Santiago Díaz-Madrigal, Alexander Vasil'ev. 2007-01-10. Digons and angular derivatives of analytic self-maps of the unit disk. https://arxiv.org/abs/math/0701272

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