@article{1077375367,
author = {Ostberg, D. R.},
title = {Relative group extensions and kernels},
journal = {Duke Math. J.},
volume = {31},
number = {1},
year = {1964},
pages = { 529-537},
language = {en},
url = {http://dml.mathdoc.fr/item/1077375367}
}
Ostberg, D. R. Relative group extensions and kernels. Duke Math. J., Tome 31 (1964) no. 1, pp. 529-537. http://gdmltest.u-ga.fr/item/1077375367/