@article{05632501, title = {Time-dependent circular billiard.}, journal = {Mathematical Problems in Engineering}, volume = {2009}, year = {2009}, doi = {10.1155/2009/531024}, zbl = {1181.37053}, language = {en}, url = {http://dml.mathdoc.fr/item/05632501} }
Howard, J.E. Time-dependent circular billiard.. Mathematical Problems in Engineering, Tome 2009 (2009) . doi : 10.1155/2009/531024. http://gdmltest.u-ga.fr/item/05632501/