1. P. A. Franken, A. E. Hill, C. W. Peters, andG. Weinreich,Phys. Rev. Lett. 7 (1961) 118?119.
2. S. A. Akhmanov andR. V. Khokhlov, ?Problemy Nyelineynoy Optiki? (Akad. Nauk SSSR, Moscow, 1964).
3. N. Bloembergen, ?Nonlinear Optics? (W. A. Benjamin, New York, 1965).
4. P. N. Butcher, ?Nonlinear Optical Phenomena? (Ohio State University, 1965).
5. G. Birnbaum, ?Optical Masers? (Academic Press, New York, 1964);V. M. Fayn andJ. I. Khanin, ?Kvantovaya Radioflzika? (Moscow, Soviet Radio, 1965).