@article{GDZPPN002213516,
title = {An example of an arithmetic Fuchsian group.},
journal = {Journal f\"ur die reine und angewandte Mathematik},
volume = {468},
year = {1995},
pages = {69-86},
zbl = {0846.12004},
url = {http://dml.mathdoc.fr/item/GDZPPN002213516}
}
Krammer, Daan. An example of an arithmetic Fuchsian group.. Journal für die reine und angewandte Mathematik, Tome 468 (1995) pp. 69-86. http://gdmltest.u-ga.fr/item/GDZPPN002213516/