@article{GDZPPN002346745,
title = {Discrete Subgroups of the Lorentz Group.},
journal = {Mathematica Scandinavica},
volume = {11},
year = {1962},
pages = {85-107},
zbl = {0118.03902},
url = {http://dml.mathdoc.fr/item/GDZPPN002346745}
}
Greenberg, Leon. Discrete Subgroups of the Lorentz Group.. Mathematica Scandinavica, Tome 11 (1962) pp. 85-107. http://gdmltest.u-ga.fr/item/GDZPPN002346745/