1. Ya. B. Zel’dovich and Yu. B. Khariton, “On the Chain Decay of the Main Uranium Isotope,” Zh. Eksp. Teor. Fiz. 9(12), 1425–1427 (1939).
2. Ya. B. Zel’dovich and Yu. B. Khariton, “On the Chain Decay of Uranium Under the Effects of Slow Neutrons,” Zh. Eksp. Teor. Fiz. 10(1), 29–36 (1940).
3. Ya. B. Zel’dovich and Yu. B. Khariton, “Kinetics of the Chain Decay of Uranium,” Zh. Eksp. Teor. Fiz. 10(5), 477–482 (1940).
4. L. I. Rusinov and G. N. Flerov, “Experiments on Uranium Fission,” Izv. Akad. Nauk SSSR, Ser. Fiz. 4(2) (1940).
5. K. A. Petrzhak and G. N. Flerov, “Spontaneous Uranium Fission,” Dokl. Akad. Nauk SSSR 28(6), 500–501 (1940).