1. E. Fiorini: to be published.
2. K. Grotz andH. V. Klapdor: this issue, p. 535.
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4. R. Davis jr.,B. T. Cleveland andJ. K. Rowley:Conference on the Interactions between Particle and Nuclear Physics, Steamboat Spring, May 23–30, 1984.
5. S. M. Bilenky andB. Pontecorvo:Phys. Rep.,41, 226 (1978).