For relatively hyperbolic groups, we investigate conditions guaranteeing that the subgroup generated by two relatively quasiconvex subgroups and is relatively quasiconvex and isomorphic to . The main theorem extends results for quasiconvex subgroups of word-hyperbolic groups, and results for discrete subgroups of isometries of hyperbolic spaces. An application on separability of double cosets of quasiconvex subgroups is included.
Eduardo Martínez-Pedroza. Alessandro Sisto. "Virtual amalgamation of relatively quasiconvex subgroups." Algebr. Geom. Topol. 12 (4) 1993 - 2002, 2012. https://doi.org/10.2140/agt.2012.12.1993