Chaotic n-Dimensional Euclidean and Hyperbolic Open Billiards and Chaotic Spinning Planar Billiards. - Ali Deniz; Judy Kennedy; Sahin Koçak; Andrei V. Ratiu; Cevat Üstün; James A. Yorke (SIAM J. Appl. Dyn. Syst., 2008)