2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/72624In this paper we study the reduction of $p$-cyclic covers of the $p$-adic line ramified at exactly four points. For $p=2$ these covers are elliptic curves and Deuring has given a criterion for when such a curve has good reduction. Here we consider the case of $p>2$ and completely determine the stable model of the cover. In particular we obtain a finite extension $R'$ of $R$ necessary for the stable reduction to be defined. No additional conditions are imposed on the geometry of the branch locus and thus this work can be viewed as a first step towards understanding the situation where branch points coalesce.12 pagesAlgebraic GeometryNumber TheoryAn analog to Deuring's criterion for good reduction of elliptic curvestext