Ph. Richter et al., ACTION INTEGRALS FOR ELLIPSOIDAL BILLIARDS, Zeitschrift fur Naturforschung. A, A journal of physical sciences, 50(8), 1995, pp. 693-710
Integrable billiards in ellipsoidal and related shapes are discussed.
The emphasis is on the computation and graphic presentation of energy
surfaces in the space of action variables. Explicit results, including
figures, are given for spheres, circular cylinders, planar ellipses,
prolate and oblate ellipsoids.