1. Hammond, R.T.: Electron. J. Theor. Phys. 7, 221 (2010)
2. Abraham, M.: Theorie der Elektrizitat, vol. II. Teubner, Leipzig (1905)
3. Lorentz, H.A.: The Theory of Electrons and Its Applications to the Phenomena of Light and Radiant Heat. Teubner, Stechert, Leipzig, New York (1909)
4. Dirac, P.A.M.: Proc. R. Soc. A, Math. Phys. Eng. Sci. 167, 148 (1938)
5. Jackson, J.D.: Classical Electrodynamics, 2nd edn. Wiley, New York (1975). The FO equation appears in the third edition