@article{01423415, title = {Doubles of groups and hyperbolic LERF 3-manifolds.}, journal = {Annals of Mathematics. Second Series}, volume = {150}, year = {1999}, pages = {775-806}, doi = {10.2307/121056}, zbl = {0944.20023}, language = {en}, url = {http://dml.mathdoc.fr/item/01423415} }
Gitik, Rita. Doubles of groups and hyperbolic LERF 3-manifolds.. Annals of Mathematics. Second Series, Tome 150 (1999) pp. 775-806. doi : 10.2307/121056. http://gdmltest.u-ga.fr/item/01423415/