1. R.J. Hughes and M.H. Holzscheiter, Phys. Rev. Lett. 66(1991)854.
2. R.J. Hughes and M.H. Holzscheiter, J. Mod. Opt. 39(1992)263.
3. R.J. Hughes, Fundamental symmetry tests with antihydrogen, Los Alamos Report LA-UR-92-4337 (1992), to be published in: Nucl. Phys. A, Special Issue, Proceedings of the Second Biennial Conference on Low Energy Antiproton Physics (LEAP'92), Courmayeur, Italy, 1992.
4. R.J. Hughes, Hyp. Int. 76(1993)3.
5. R.J. Hughes, in:Low Energy Antiproton Physics, eds. P. Carlson et al. (World Scientific, Singapore, 1991) p. 425;AIP Conf. Proc. 243: Intersections Between Particle and Nuclear Physics, ed. W.T.H. Van Oers (AIP, New York, 1992) p. 331.