1. Direct Experiments on Double Beta Decay;Fiorini,1984
2. Double Beta Decay: Current Status;Caldwell,1985
3. D.O. Caldwell, et al., Half-life on the Zero-Neutrino and Two-Neutrino Double Beta Decay of 76Ge, preprint.
4. The Milano Experiment on 76Ge and 136Xe Double Beta Decay;Belloti,1985
5. E. Bellotti et al., Proposal to the Int. Sci. Comm. of the Gran Sasso Laboratory for an Experiment on Double Beta Decay.