1. Delone, N.B. and Krainov, V.P. (1994) Multiphoton processes in atoms, Springer-Verlag, Berlin.
2. Bashkansky, M., Bucksbaum, P.H., and Schumacher, D.W. (1988) Phys. Rev. Lett. 60, 2458–2462.
3. Manakov, N.L., Ovsiannikov, V.D., and Rapoport, L.P. (1986) Atoms in a laser field, Phys. Rep. 141, 319–433.
4. Berestetskii, V.B., Lifshitz, E.M., and Pitaevskii, L.P. (1982) Quantum electrodynamics, Pergamon Press, Oxford.
5. Manakov, N.L. and Fainshtein, A.G. (1984) Zh. Ehsp, Teor. Fiz. 87, 1552–1564.