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arXiv · 1504.02928

Spherical quadrilaterals with three non-integer angles

Alexandre Eremenko·Andrei Gabrielov·Vitaly Tarasov
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Abstract

We classify spherical quadrilaterals up to isometry in the case when one inner angle is a multiple of pi while the other three are not. This is equivalent to classification of Heun's equations with real parameters and one apparent singularity such that the monodromy consists of unitary transformations.

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Alexandre Eremenko, Andrei Gabrielov, Vitaly Tarasov. 2015-04-12. Spherical quadrilaterals with three non-integer angles. https://arxiv.org/abs/1504.02928

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