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4. CDHS Collaboration, Proceedings of Neutrino 79, International Conference on Neutrinos, Weak Interactions and Cosmology (Bergen, 1979, ed. A. Haatuft and C. Jarlskog), Vol. 2, p. 92.
5. For a recent discussion see e.g. G. H. Trilling’s rapporteur talk at the XX International Conference on High Energy Physics at Madison (July, 1980 ).