@article{oai:yamagata.repo.nii.ac.jp:00003051,
 author = {井上,  彰夫 and 井伊,  清隆},
 issue = {2},
 journal = {山形大学紀要. 自然科学 = Bulletin of Yamagata University. Natural Science},
 month = {Feb},
 note = {論文(Article), We answer the question whether a billiard system is a new integrable system or not. This question is posed by H. J. Korsch, H.-J. Jodl, and T. Hartmann in [1],[2]. The answer is NO, that is, the billiard system is nothing but an elliptic billiard system, which is well-known to be integrable.},
 pages = {41--44},
 title = {あるビリヤード力学系の積分可能性について},
 volume = {17},
 year = {2011}
}