Good articles: R. Evan Wallace and C. Schroeder Analysis of Billiard Ball Collisions in Two Dimensions Am. J. Phys. 56, 815, 1988. George Y. Onoda Am. J. Phys. 57, 476, 1989.
The Physics of Pocket Billiards Wayland C. Marlowe available now from the author Wayland C. Marlowe 14645 Black Bear Road Palm Beach Gardens, FL 33418-8606 $32.45 or call American Institute of Physics 1-800-809-2247
The Science of Pocket Billiards Jack H. Koehler Sportology Publications 25832 Evergreen Rd. Laguna Hills, CA 92653 $32.04 with shipping and tax This one belongs on your shelf along with Byrne's Advanced Techniques and Fel's Mastering Pool.