Hofer H, Wysocki K, Zehnder E. Unknotted periodic orbits for Reeb flows on the three-sphere. TMNA [Internet]. 1996 Jun. 1 [cited 2024 Jul. 22];7(2):219-44. Available from: https://apcz.umk.pl/TMNA/article/view/TMNA.1996.010