1. R. E. Barber,Bell System Techn. J.,50, No.3, 881 (1971).
2. D. E. Vakman,Radiotekhnika i Elektronika,24, No. 5, 982 (1979).
3. D. Gabor,J. Inst. Elec. Eng.,46, No. 3, 26, 429 (1946).
4. L. A. Vainshtein and D. E. Vakman,Frequency Separation in Oscillation Theory [in Russian], Nauka, Moscow (1983).
5. L. M. Fink,Signals, Noise, and Errors [in Russian], Svyaz', Moscow (1978).