# All Questions

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### existence of infinite abelian subgroup in infinite locally compact groups

1) Let $G$ be an infinite locally compact group. Does there exist an infinite abelian locally compact subgroup of $G$? Rem: I know that there exists an infinite abelian subgroup in every infinite ...
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### On order automorphisms group of some abelian group

Please determine order The automorphisms group of the group $Z_{8}\times Z_{4}$, where $Z_{8}$ and $Z_{4}$ are cyclic groups of order $8$ and $4$, respectivly.
I was recently reading this paper by Weston, whereby he talks about the modular curves $X_0(11)$ and $X_1(11)$. I was wondering if anyone can recommend a more general exposition of modular curves ...