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On a result of Miyanishi-Masuda

Hubert Flenner·Mikhail Zaidenberg
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Abstract

Let $X$ be an affine surface admitting a unique affine ruling and a $\mathbb C^*$-action. Assume that the ruling has a unique degenerate fibre and that this fibre is irreducible. In this paper we give a short proof of the following result of Miyanishi and Masuda: the universal covering of $X$ is a hypersurface in the affine 3-space given by the equation $x^my=z^d-1$, where $m>1$.

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Hubert Flenner, Mikhail Zaidenberg. 2005-06-13. On a result of Miyanishi-Masuda. https://arxiv.org/abs/math/0506235

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