Soiuz Pisatelei, Soviet literature, Issues 1-6, p 188, Foreign Languages Publishing House, 1982.
James T. Andrews, “Red cosmos: K.E. Tsiolkovskii, grandfather of Soviet rocketry”, Issue 18 Centennial of Flight Series, p 114, Texas A&M University Press, 2009, ISBN1-60344-168-9, ISBN978-1-60344-168-1