The following is a paper by H. Aspden published in Lettere al Nuovo Cimento, v. 39, pp. 247-251 (1984).
Abstract: Alternative explanations for free-electron diamagnetism appear paradoxical and inconsistent with the reactive induction properties of magnetic materials. It is shown that the paradox can be eliminated by a generalized definition of the magnetic field with interesting spin-off consequences, including a justification for the anomalous doubling of the positron's effective mass in a free-electron environment.
Commentary: Here, once again, the author drew attention to his theme on diamagnetic reaction as the clear evidence of the need for an aether capable of justifying the g-factor of 2. This time, however, the author pointed to its relevance to positron reaction properties. Whereas Dirac-type theory implies symmetry, the experiments reveal the asymmetry which this author's theory implies.