Reflective and quasi-reflective Bianchi groups
arXiv:1210.2759
Abstract
A discrete subgroup of the group of isometries of the hyperbolic space is called reflective if up to a finite index it is generated by reflections in hyperplanes. The main result of this paper is a complete classification of the reflective (and quasi-reflective) subgroups among the Bianchi groups and their extensions.
arXiv comment18 pages, 4 figures; revised following referees comments; to appear in Transform. Groups