1. T. E. Allibone,Lightning, edited by R. H. Golde (Academic, London, 1977), Vol. 1, pp. 231–280.
2. H. Raether,Electron Avalanches and Breakdown in Gases(Butterworth, London, 1964), pp. 124–153.
3. J. M. Meeks and J. D. Craggs,Electrical Breakdown of Gases(Clarendon, Oxford, 1953), Chap. VI.