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On Extremal Contractions from Threefolds to Surfaces: the Case of One non-Gorenstein Point

Yuri G. Prokhorov
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Abstract

Let $f\colon X\to S$ be an extremal contraction from a threefold with only terminal singularities to a surface. We study local analytic structure such contractions near degenerate fiber $C$ in the case when $C$ is irreducible and $X$ has on $C$ only one non-Gorenstein point.

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BibTeXRIS

Yuri G. Prokhorov. 1997-02-17. On Extremal Contractions from Threefolds to Surfaces: the Case of One non-Gorenstein Point. https://arxiv.org/abs/alg-geom/9605002

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