1. See for instance S. Frankel, “Rare and Ultrarare Muon Decays”, in “Muon Physics”, V.W. Hughes and C.S. Wu, Editors, Academic Press, New York (1975)
2. S.H. Neddermeyer and C.D. Anderson, Phys. Rev. 51, 884 (1937)
3. M. Conversi et al., Phys. Rev. 71, 209 (1947)
4. H. Yukawa, Proc. Phys. Math. Soc. Jpn 17, 48 (1935)
5. E.P. Hincks and B. Pontecorvo, Phys. Rev. 73, 257 (1948)