1. Babikov, V.V., Metod fazovykh funktsiy v kvantovoy mekhanike (Phase Function Method in Quantum Mechanics), Moscow: Nauka, 1976.
2. Sedrakian, D.M. and Khachatrian, A.Zh., Astrophysics., 1999, vol. 42, p. 316.
3. Sedrakian, D.M. and Khachatrian, A.Zh., J. Contemp. Phys. (Armenian Ac. Sci.), 1999, vol. 34, no. 3, p. 7.
4. Sedrakian, D.M. and Khachatrian, A.Zh., Phys. Lett. A, 2000, vol. 265, p. 294.
5. Sedrakian, D.M. and Khachatrian, A.Zh., Ann. Phys., 2002, vol. 11, p. 503.