Kaloshin V, Sorrentino A. 2018. On the integrability of Birkhoff billiards. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences. 376(2131), 20170419.
LibreCat: https://research-explorer.ista.ac.at/record/8419
DOI: 10.1098/rsta.2017.0419