// <I>ISRSSP' 2014<D> : Proceedings of the Fourth international symposium on "Radio systems and space plasma", Ruse, Bulgaria, 30-31 october 2014. - Sofia : [IICREST], 2014, p. 55-62.
A. Borodzhieva; Ts. I. Vasilev; S. D. Kostadinov;
P. Manoilov;
G. Marinova и др.