1988 · J. Gegenberg, P. F. Kelly, et al. · Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields · 48
1989 · J. Gegenberg, P. F. Kelly, et al. · Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields · 5