@article{10_4153_CJM_1980_019_6,
     author = {O'Malley, Thomas J.},
     title = {S-Subgroups of the {Real} {Hyperbolic} {Groups}},
     journal = {Canadian journal of mathematics},
     pages = {246--256},
     year = {1980},
     volume = {32},
     number = {1},
     doi = {10.4153/CJM-1980-019-6},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1980-019-6/}
}