1. Super-Kamiokande collaboration, Y. Fukuda et al., Evidence for oscillation of atmospheric neutrinos, Phys. Rev. Lett. 81 (1998) 1562 [ hep-ex/9807003 ] [ INSPIRE ].
2. SNO collaboration, Q.R. Ahmad et al., Direct evidence for neutrino flavor transformation from neutral current interactions in the Sudbury Neutrino Observatory, Phys. Rev. Lett. 89 (2002) 011301 [ nucl-ex/0204008 ] [ INSPIRE ].
3. M. Mezzetto Experimental outlook, in Neutrino 2016, July 4-9, London, U.K. (2016).
4. E. Majorana, Teoria simmetrica dell’elettrone e del positrone, Nuovo Cim. 14 (1937) 171 [ INSPIRE ].
5. S.M. Bilenky, J. Hosek and S.T. Petcov, On oscillations of neutrinos with Dirac and Majorana Masses, Phys. Lett. 94B (1980) 495 [ INSPIRE ].