1. A. Benvenuti et al.: Phys. Rev. Lett.,34, 597 (1975). See also,D. Cline:Multi Lepton Production by Neutrinos and Antineutrinos:Charm,Charm-Changing Neutral Currents and New Flavours, talk given at the BNL APS meeting, October 1976, published in the proceedings (1976) andO. Fackler, talk given at the same meeting,M. Holder,M. J. Knobloch,J. May,H. P. Paar,P. Palazzi,D. Schlatter,J. Steinberger,H. Suteb,H. Wahl,E. G. H. Williams,F. Eisele,G. Geweniger,K. Kleiknecht,G. Spahn,H. J. Willutzki,W. Dorth F. Dydak,V. Hepp,K. Tittel,J. Wotschack,P. Bloch,B. Devaux,M. Grimm,J. Maillard,B. Petaiid,J. Rander,A. Savoy-Navarro,R. Turlay, andF. L. Navarria:Phys. Lett. B,70, 396 (1977);A. Benvenuti,F. Bobisut,D. Cline,P. S. Cooper,M. G. D. Gilchriese,S. M. Heagt,R. Imlay,M. Johnson,T. Y. Ling,R. Lundy,A. K. Mann,P. McIntyre,S. Mori,D. D. Reeder,J. Rich,R. Stefanski andD. R. Winn:Phys. Rev. Lett.,41, 725 (1978).
2. K. Nishikawa, D. Buchholz, B. G. Barish, J. F. Bartlett, R. Blair, Y. Chu, J. Lee, P. Linsay, J. Ludwig, R. Messner, P. Mine, F. J. Sciulli, M. Shaevitz, E. Siskind, D. Edwards, H. Edwards, H. E. Fisk, Y. Fukushima, G. Krafczyk, D. Nease, A. Bodek, W. Marsh andO. Fackler:Phys. Rev. Lett.,46, 1555 (1981);M. Jonker et al.: Phys. Rev. Lett. B,197, 241 (1981);T. Trinko et al.: Phys. Rev. D,19, 1889 (1981). The HPWF group carried out the only measurement with targets of greatly different density to directly « measure » the rate of π →υ decays in the neutrino interactions.
3. E. Fisk:Proceedings of the International Symposium on Lepton and Photon Interactions at High Energy, Bonn, 1981 (University of Bonn, 1981), p. 703.M. J. Murtagh:Proceedings of the International Symposium on Lepton and Photon Interactions at High Energy, Batavia 1979 (FNAL, Batavia, 111., 1979), p. 277.
4. V. V. Ammosov, A. G. Denisov, P. F. Ermolov, G. S. Gapienko, V. A. Gapienko, V. I. Klyukhin, V. I. Koreshev, P. V. Pittukhin, V. I. Sirotenko, E. A. Slobodyuk, Z. U. Usujbov, V. G. Zaetz, J. P. Berge, D. Bogebt, R. Endorf, R. Hanft, J. A. Malko, F. A. Nezrick, R. Orava, V. I. Efremenko, A. V. Fedotov, P. A. Gorichev, V. S. Kaftanov, G. K. Kliger, V. Z. Kolganov, S. P. Krutchinin, M. A. Kubantsev, I. V. Makhlueva, V. I. Shekeljan, V. G. Shevchenko, J. Bell, C. T. Coffin, B. P. Roe, A. A. Seidl, D. Sinclair andE. Wang:Phys. Lett. B,106, 151 (1981).
5. A. Haatuff et al. :Dilepton and Trilepton Production by Neutrinos in Gargamelle at CERN SPSEnergies, CERN-EP/83, January 16–31, 1983.