@article{01751250,
title = {Subgroups of finite index in an additive group of a ring.},
journal = {International Journal of Mathematics and Mathematical Sciences},
volume = {25},
year = {2001},
pages = {83-89},
doi = {10.1155/S0161171201010274},
zbl = {1016.16011},
language = {en},
url = {http://dml.mathdoc.fr/item/01751250}
}
Mojdeh, Doostali; Hashemi, S.Hassan. Subgroups of finite index in an additive group of a ring.. International Journal of Mathematics and Mathematical Sciences, Tome 25 (2001) pp. 83-89. doi : 10.1155/S0161171201010274. http://gdmltest.u-ga.fr/item/01751250/