1. A Einstein, B Podolsky and N Rosen,Phys. Rev. 47, 777 (1935)
2. Cs Ferencz,Elektromágneses hullámterjedés, ‘Electromagnetic wave propagation’, in Hungarian (Academic Press, Budapest, 1996)
3. H Osterberg,J. Opt. Soc. Am. 48, 513 (1958)
4. M A Heald and C B Wahrton,Plasma diagnostics with microwaves (John Wiley & Sons, New York, 1965)
5. K G Budden,Radio waves in the ionosphere (Cambridge University Press, London, 1966)