@article{GDZPPN002319446,
title = {A Short Proof of the Rydakov-Safarevic Theorem.},
journal = {Mathematische Annalen},
volume = {250},
year = {1980},
pages = {171-174},
zbl = {0457.14018},
url = {http://dml.mathdoc.fr/item/GDZPPN002319446}
}
Lang, William E.; Nygaard, Niels O. A Short Proof of the Rydakov-Safarevic Theorem.. Mathematische Annalen, Tome 250 (1980) pp. 171-174. http://gdmltest.u-ga.fr/item/GDZPPN002319446/