1. For a detailed account of the actual events leading up to the launch of Sputnik, see A.A. Siddiqi, Iskusstvennyy sputnik zemli: The launch of the World's first artificial satellite 50 years ago, Spaceflight 49 (2007) 426–442.
2. Ot pervykh ballisticheskikh do…;Mozzhorin;Aviatsiya i Kosmonavtika,1991
3. For details, see A.A. Siddiqi, Sputnik and the Soviet Space Challenge, University Press of Florida, Gainesville, 2003, pp. 84–86.
4. V. Baberdin, Zdes’ nachinalsya voyenny kosmos, Krasnaya Zvezda April 30 (1994) 4;
5. I. Yatsunskiy, O deyatel’nosti M.K. Tikhonravova v period s 1947 po 1953 gg. po obosnovaniyu vozmozhnosti sozdaniya sostavykh raket, Iz Istorii Aviatsii i Kosmonavtiki 42 (1980) 31–38.