arXiv · 1306.0033
It is shown that for any finitely generated subgroups H and K of a free group F, and for any element g in F the double coset HgK is closed in the profinite topology of F.
Rita Gitik, Eliyahu Rips. 2013-05-31. On double cosets in free groups. https://arxiv.org/abs/1306.0033
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