@article{GDZPPN002318997, title = {Cohomology of Congruence Subgroups of SL (n,Z).}, journal = {Mathematische Annalen}, volume = {250}, year = {1980}, pages = {55-74}, zbl = {0438.20035}, url = {http://dml.mathdoc.fr/item/GDZPPN002318997} }
Ash, Avner. Cohomology of Congruence Subgroups of SL (n,Z).. Mathematische Annalen, Tome 250 (1980) pp. 55-74. http://gdmltest.u-ga.fr/item/GDZPPN002318997/