1. J.D. Jackson, Classical Electrodynamics, formula 14.114, second edition John Wiley and Sons 1975, p. 681.
2. J. Weber, General Relativity and Gravitational Waves, chapter 8, Interscience-Wiley, New York, London, 1961.
3. J. Weber, Physics Letters 81A, 9, 542, 23 February, 1981.
4. Gravitational Radiation and Relativity, Volume 3, Proceedings of the Sir Arthur Eddington Centenary Symposium, edited by J. Weber, T.M. Karade, World Scientific, 1986.