arXiv · math/0201002
We prove that for a finitely generated subgroup $H$ of a word-hyperbolic group $G$ the Frattini subgroup $F(H)$ of $H$ is finite.
Ilya Kapovich. 2001-12-31. The Frattini subgroup for subgroups of hyperbolic groups. https://arxiv.org/abs/math/0201002
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