1. M. Aglietta et al. Nuovo Cimento C9,185 (1986).
2. A. Alessandrello et al Nucl. Phys. A478, 453C (1988).
3. E. Amaldi and G. Pizzella Nuovo Cimento 9C, 612 (1986).
4. E. Aprile and V.H.-M. Ku, J. Parle Columbia University Preprint n. 342 ( 1987) and private communication.
5. F. Avignone et al. Proceedings of an International Workshop on Neutrino Physics—Ed. H.V. Klapdor and B. Povh—Heidelberg Oct. 20/22, 1987 Springe—Verlag, pag. 191.