标题： 广义Seifert纤维空间的分类 显示英文标题

标题： Classification of generalized Seifert fiber spaces

摘要： 我们提供了广义Seifert纤维空间的符号分类，这些空间由Mitsuishi和Yamaguchi在坍塌Alexandrov$3$-空间的分类中引入。 此外，我们证明了非流形广义Seifert纤维空间的规范双重分支覆盖是一个Seifert流形，并用原始空间的符号不变量计算其符号不变量。 显示英文摘要

摘要： We provide a symbolic classification of generalized Seifert fiber spaces, which were introduced by Mitsuishi and Yamaguchi in the classification of collapsing Alexandrov $3$-spaces. Additionally, we show that the canonical double branched cover of a non-manifold generalized Seifert fiber space is a Seifert manifold and compute its symbolic invariants in terms of those of the original space.