@article{1104179142,
author = {Stojanov, Luchezar},
title = {An estimate from above of the number of periodic orbits for semi-dispersed billiards},
journal = {Comm. Math. Phys.},
volume = {120},
number = {3},
year = {1989},
pages = { 217-227},
language = {en},
url = {http://dml.mathdoc.fr/item/1104179142}
}
Stojanov, Luchezar. An estimate from above of the number of periodic orbits for semi-dispersed billiards. Comm. Math. Phys., Tome 120 (1989) no. 3, pp. 217-227. http://gdmltest.u-ga.fr/item/1104179142/