@article{GDZPPN002104245,
title = {Schwarz's lemma for circle packings.},
journal = {Inventiones mathematicae},
volume = {88},
year = {1987},
pages = {271-290},
zbl = {0634.30009},
url = {http://dml.mathdoc.fr/item/GDZPPN002104245}
}
Rodin, B. Schwarz's lemma for circle packings.. Inventiones mathematicae, Tome 88 (1987) pp. 271-290. http://gdmltest.u-ga.fr/item/GDZPPN002104245/