1. XXV.Deviations from Paschen's law
2. The sparking potential of mercury vapour
3. J.J. and Thomson , G.P. 1933.Conduction of Electricity through Gases, 3rd edit, Vol. ii, 476–487. Cambridge University Press.
4. Jones , F. Llewellyn and Galloway , R. 1933.Conduction of Electricity through Gases, 3rd edit, Vol. ii, 476–487. Cambridge University Press.