1. A. A. Mityureva and V. V. Smirnov, Opt. Spektrosk. 99(1), 8 (2005) [Opt. Spectrosc. 99 (1), 4 (2005)].
2. L. D. Landau and E. M. Lifshitz, Course of Theoretical Physics, Vol. 3: Quantum Mechanics: Non-Relativistic Theory, 4th ed. (Nauka, Moscow, 1989; Pergamon, New York, 1977).
3. I. Bray and A. T. Stelbovics, Phys. Rev. A 46(11), 6995 (1992).
4. A. A. Mityureva and V. V. Smirnov, Opt. Spektrosk. 101(3), 360 (2006) [Opt. Spectrosc. 101 (3), 338 (2006)].
5. A. A. Mityureva and V. V. Smirnov, Opt. Spektrosk. 74, 6 (1993) [Opt. Spectrosc. 74, 2 (1993)].