1. C. M. G. Lattes,Topics on Cosmic Rays, Editora da UNICAMP, Campinas, 1984.
2. National Academy of Sciences-National Research Council,The Biological Effects of Atomic Radiation, Summary Reports, Washington,1 (1956).
3. A. Aron,An. Acad. Brasil. Ciênc.,28, 423 (1956).
4. G. Kegel,An. Acad. Brasil. Ciênc.,28, 447 (1956).
5. E. Penna Franca, A. Pinto Coelho, and C. Chagas,An. Acad. Brasil. Ciênc.,29, 553 (1957).