@article{10_4153_CJM_1980_012_5,
     author = {Perkel, Manley},
     title = {A {Characterization} of {PSL(2,} 31) and its {Geometry}},
     journal = {Canadian journal of mathematics},
     pages = {155--164},
     year = {1980},
     volume = {32},
     number = {1},
     doi = {10.4153/CJM-1980-012-5},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1980-012-5/}
}