@article{1077474679, author = {Lyndon, Roger C.}, title = {The cohomology theory of group extensions}, journal = {Duke Math. J.}, volume = {15}, number = {1}, year = {1948}, pages = { 271-292}, language = {en}, url = {http://dml.mathdoc.fr/item/1077474679} }
Lyndon, Roger C. The cohomology theory of group extensions. Duke Math. J., Tome 15 (1948) no. 1, pp. 271-292. http://gdmltest.u-ga.fr/item/1077474679/