1. G. S. Landsberg, Optics, 6th ed. (Fizmatlit, Moscow, 2003) [in Russian].
2. S. G. Rautian, G. I. Smirnov, and A. M. Shalagin, Nonlinear Resonances in Atomic and Molecular Spectra (Nauka, Novosibirsk, 1979) [in Russian].
3. V. S. Letokhov and V. P. Chebotaev, Nonlinear Ultra High Resolution Laser Spectroscopy (Nauka, Moscow, 1990) [in Russian].
4. S. G. Rautian and A. M. Shalagin, Kinetic Problems of Nonlinear Spectroscopy (North-Holland, Amsterdam, 1991).
5. M. P. Chaika, Interference of Degenerate Atomic States (Leningr. Gos. Univ., Leningrad, 1975) [in Russian].