1. Cosmic-Ray Experiments at High Altitudes over a Wide Range of Latitudes
2. Chapman S., Bartels J.Geomagnetism. The Clarendon Press, Oxford 1940a; II: 648–648, and Vol. I, 96; 1940 b,Ibid., Vol. I, 115; 1940 c,Ibid., Vol. I, 99.
3. Results of the Dutch Cosmic Ray Expedition 1933
4. Committee on Biological Effects of Atomic Radiation.Biological Effects of Atomic Radiation, A Report to the Public. National Academy of Science and the National Research Council, Washington, D.C. 1956; 4–4
5. Committtee on Genetic Effects of Atomic Radiation.Biological Effects of Atomic Radiation, Summary Reports. National Academy of Science and the National Research Council, Washington, D.C. 1956; 23–23, 28