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2. G. W. Gaffney, Phys. Rev. 161 (1967) 1599.
3. N. de Botton, report, this conference.
4. P. De Baenst, Nucl. Phys. B24 (1970) 633, keeping terms to order (mπ/mn) in Eq. (9), which may be more consistent, obtained 13.0 and 19.9 for these numbers. It can be seen from this that the deviations between theory and experiment are of order (mπ/mn).
5. C. Tzara, Workshop on “Few Body Systems and Electromagnetic Interactions,” Frascati, March 1978.