[命题] 紧致黎曼曲面之间的每个非常值全纯映射都是有限层(分歧)覆盖映射.
[命题] 紧致黎曼曲面之间的每个非常值全纯映射都是有限层(分歧)覆盖映射.
Every non-constant holomorphic mapping between compact Riemann surfaces is a finite-sheeted (ramified) covering map.
见 [1] pp.15 Example.
[1] Hershel M. Farkas, Irwin Kra, Riemann Surfaces, 2nd edition. GTM 71.