@article{01278974,
title = {Hard ball systems are completely hyperbolic.},
journal = {Annals of Mathematics. Second Series},
volume = {150},
year = {1999},
pages = {35-96},
doi = {10.2307/121019},
zbl = {0918.58040},
language = {en},
url = {http://dml.mathdoc.fr/item/01278974}
}
Simányi, Nándor; Szász, Domokos. Hard ball systems are completely hyperbolic.. Annals of Mathematics. Second Series, Tome 150 (1999) pp. 35-96. doi : 10.2307/121019. http://gdmltest.u-ga.fr/item/01278974/