September 2010]. (原始内容存档 (PDF)于2011-09-28). Strauss, Robert. Following the BouncingBall. The New York Times. 28 January 2001 [21 June 2010]. (原始内容存档于2021-11-23)
of a bouncingball is described for several common ball types having different bounce characteristics. Results are presented for a tennis ball, a baseball