1. Abramowitz M, Stegun IA (1964) Handbook of Mathematical Functions. Dover Publications, New York
2. Akhmetov DG (2009) Vortex Rings. Springer, Berlin
3. Berezovski A, Kaplanski F (1988) Diffusion of a ring vortex. Fluid Dyn 22:832–836
4. Berezovski A, Kaplanski F (1995) Vorticity distributions for thick and thin viscous vortex rings and pairs. Arch Mech 47(6):1015–1026
5. Cantwell BJ (2002) Introduction to Symmetry Analysis. Cambridge University Press, Cambridge