@article{01893530, title = {Lifting M\"obius groups.}, journal = {The New York Journal of Mathematics [electronic only]}, volume = {8}, year = {2002}, pages = {181-188}, zbl = {1066.30038}, language = {en}, url = {http://dml.mathdoc.fr/item/01893530} }
Button, J. O. Lifting Möbius groups.. The New York Journal of Mathematics [electronic only], Tome 8 (2002) pp. 181-188. http://gdmltest.u-ga.fr/item/01893530/