1. E. Majorana, Theory of the Symmetry of Electrons and Positrons, Nuovo Cim. 14 (1937) 171 [ INSPIRE ].
2. V.A. Kuzmin, CP-noninvairiance and Baryon Asymmetry of the Universe JETP Lett. 12 (1970) 228.
3. S.L. Glashow, Proceedings of Neutrino’79, International conference on neutrinos, weak interactions and cosmology, Bergen, Norway (1979), A. Haatuft and G. Jarlskog eds., University of Bergen, Bergen, Norway, 1 (1980) 518.
4. R.N. Mohapatra and R.E. Marshak, Local B-L Symmetry of Electroweak Interactions, Majorana Neutrinos and Neutron Oscillations, Phys. Rev. Lett. 44 (1980) 1316 [Erratum ibid. 44 (1980) 1643] [ INSPIRE ].
5. Yu.G. Abov, F.S. Dzheparov and L.B. Okun, Test of the equality of the particle and antiparticle masses in neutron-antineutron oscillations, JETP Lett. 39 (1984) 493.