1. SNO Collab. (Q. R. Ahmad et al.), Phys. Rev. Lett. 87, 071301 (2001); 89, 011301, 011302 (2002).
2. KamLAND Collab. (K. Eguchi et al.), Phys. Rev. Lett. 90, 021802 (2003).
3. M. Raidal, Phys. Rev. Lett. 93, 161801 (2004).
4. O.M. Boyarkin, Physics of Massive Neutrinos, 2nd ed. (URSS, Moscow, 2006) [in Russian].
5. R. N. Mohapatra and J. C. Pati, Phys. Rev. D 11, 566 (1975); R. N. Mohapatra and G. Senjanovic, Phys. Rev. D 23, 165 (1981); O. M. Boyarkin, Phys. Rev. D 50, 2247 (1994).