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2. D. H. Madison and E. Merzbacher, in Atomic Inner Shell Processes, Vol. I, B. Craseman, Ed., Academic Press, New York (1975), p. 1.
3. E. J. McGuire, Phys. Rev. A 3, 267 (1971), and private communication;
4. E. J. McGuire, Phys. Rev. A Ibid. 16, 62, 73 (1977);
5. E. J. McGuire, Phys. Rev. A 25, 192 (1982).