1. H.E. Johns and J.S. Laughlin, in “Radiation Dosimetry”, G.J. Hine and G.L. Brownell (eds.), Academic Press, New York, 1956, chapter 2.
2. J.W.T. Spinks and R.J. Woods, “An Introduction to Radiation Chemistry”, 2nd edn., Wiley-Interscience, Toronto, 1976, P. 29.
3. D.E. Lea, “Actions of Radiations on Living Cells”, 2nd edn., Cambridge University Press, 1955, chapter 1.
4. G.R. Freeman and J.M. Faydh, J. Chem. Phys. 43, 86 (1965).
5. G.R. Freeman, “Radiation Chemistry”, Quaderni de la Ricerca Scientifica, no. 67, Rome, 1970, p. 45, and assume that E ≈ 20 eV is needed to produce an ion-electron pair.