@article{MZM_1994_55_3_a13,
     author = {A. A. Panov},
     title = {Elliptical billiard table with {Newtonian} potential},
     journal = {Matemati\v{c}eskie zametki},
     pages = {139--140},
     year = {1994},
     volume = {55},
     number = {3},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1994_55_3_a13/}
}