@article{GDZPPN002102978, title = {On the congruence subgroup problem, II.}, journal = {Inventiones mathematicae}, volume = {83}, year = {1986}, pages = {73-118}, zbl = {0603.20044}, url = {http://dml.mathdoc.fr/item/GDZPPN002102978} }
Raghunathan, M.S. On the congruence subgroup problem, II.. Inventiones mathematicae, Tome 83 (1986) pp. 73-118. http://gdmltest.u-ga.fr/item/GDZPPN002102978/