@article{RM_2005_60_2_a14,
     author = {L. D. Pustyl'nikov},
     title = {Generalized {Newtonian} periodic billiards in~a~ball},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {365--366},
     publisher = {mathdoc},
     volume = {60},
     number = {2},
     year = {2005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_2005_60_2_a14/}
}