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Exceptional quotient singularities

D. Markushevich·Yu. G. Prokhorov
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Abstract

A singularity is said to be exceptional (in the sense of V. Shokurov), if for any log canonical boundary, there is at most one exceptional divisor of discrepancy -1. In our previous paper (math.AG/9805004) we found two examples of exceptional canonical singularities: these are quotients by Klein's simple group of order 168 or by its central extension of order 504. Now we classify all the three-dimensional exceptional quotient singularities.

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D. Markushevich, Yu. G. Prokhorov. 1998-06-13. Exceptional quotient singularities. https://arxiv.org/abs/math/9806029

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