1. C. M. Bowden and J. P. Dowling, Phys. Rev. A 47: 1247 (1993).
2. H. A. Lorentz, Weedem. Ann. 9: 641 (1880);
3. L. Lorenz, ibid. 11: 70 (1881).
4. J. D. Jackson, “Classical Electrodynamics,” 2nd Ed., Wiley, NY (1964), Chap. 4.
5. M. Born and E. Wolf, “Principles of Optics,” McMillan, NY (1964), Chap. 2.