1. E. A. Vasil’tsov, Contactless Seals [in Russian], Mashinostroenie, Leningrad (1974), p. 156.
2. L. A. Kondakov, Working Fluids and Seals of Hydraulic Systems [in Russian], Mashinostroenie, Moscow (1982), p. 217.
3. G. V. Makarov, Sealing Devices, 2nd ed., [in Russian], Mashinostroenie, Leningrad (1973), p. 232.
4. V. A. Martsinkovskii, Slit Seals: Theory and Practice [in Russian], Sumy State University Press, Sumy (2005), p. 416.
5. A. I. Golubev and L. A. Kondakov (eds.), Seals and Sealing Engineering: A Handbook [in Russian], Mashinostroenie, Moscow (1986), p. 464.