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Journal of the American Mathematical Society

Published by the American Mathematical Society, the Journal of the American Mathematical Society (JAMS) is devoted to research articles of the highest quality in all areas of mathematics.

ISSN 1088-6834 (online) ISSN 0894-0347 (print)

The 2020 MCQ for Journal of the American Mathematical Society is 4.83.

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Three point covers with bad reduction
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by Stefan Wewers
J. Amer. Math. Soc. 16 (2003), 991-1032
Published electronically: July 8, 2003


We study Galois covers of the projective line branched at three points with bad reduction to characteristic $p$, under the condition that $p$ strictly divides the order of the Galois group. As an application of our results, we prove that the field of moduli of such a cover is at most tamely ramified at $p$.
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Bibliographic Information
  • Stefan Wewers
  • Affiliation: Mathematisches Institut, Beringstr. 1, 53115 Bonn, Germany
  • MR Author ID: 652833
  • Email:
  • Received by editor(s): January 10, 2003
  • Published electronically: July 8, 2003
  • © Copyright 2003 American Mathematical Society
  • Journal: J. Amer. Math. Soc. 16 (2003), 991-1032
  • MSC (2000): Primary 14H30, 11G20
  • DOI:
  • MathSciNet review: 1992833