@article{BAG_1990__30_138464,
     author = {K. Bezdek},
     title = {On billiard arcs},
     journal = {Beitr\"age zur Algebra und Geometrie},
     pages = {155--166},
     year = {1990},
     volume = {30},
     url = {http://geodesic.mathdoc.fr/item/BAG_1990__30_138464/}
}