@article{10_4153_CJM_2009_067_6,
     author = {Will, Pierre},
     title = {Traces, {Cross-Ratios} and {2-Generator} {Subgroups} of {SU(2,} 1)},
     journal = {Canadian journal of mathematics},
     pages = {1407--1436},
     year = {2009},
     volume = {61},
     number = {6},
     doi = {10.4153/CJM-2009-067-6},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-2009-067-6/}
}