• A model for the formation of "optimal" vortex rings with taking into account viscosityKaplanski, Felix; Rudi, Ülo21st International Congress of Theoretical and Applied Mechanics : August 15-21, 2004, Warsaw, Poland : ICTAM04 : abstracts and CD-ROM proceedings2004 / p. 189 https://pubs.aip.org/aip/pof/article/17/8/087101/361381/A-model-for-the-formation-of-optimal-vortex-rings