The following is a paper by Harold Aspden published in Physics Essays, volume 8, pp. 19-28 (1995).

'Retardation in the Coulomb Potential'

Abstract: The spatial disposition of field energy owing to mutual interaction of two particles is usually considered in retarded force interaction theories. Stimulated by a comment from Allen [Physics Essays, v. 6, p. 614 (1993)], the author briefly summarizes his own prior published analysis of the electrostatic, electromagnetic, and gravitational field energy distributions and their bearing on action-at-a-distance theories.
The full text of this paper may also be seen in PDF format as Paper No. 14 [1995e] in the Appendix to the author's 1996 book: Aether Science Papers.