@article{10_2307_121056,
     author = {Rita Gitik},
     title = {Doubles of groups and hyperbolic {LERF} \(3\)-manifolds},
     journal = {Annals of mathematics},
     year = {1999},
     volume = {150},
     number = {3},
     doi = {10.2307/121056},
     zbl = {0944.20023},
     url = {http://geodesic.mathdoc.fr/articles/10.2307/121056/}
}