B.D. Zaitsev – Professor, Main Research Scientist, 

Saratov branch of Kotel’nikov IRE of RAS

E-mail: zai-boris@yandex.ru

A.P. Semyonov – Ph.D.(Phys.-Math.), Senior Research Scientist, 

Saratov branch of Kotel’nikov IRE of RAS

E-mail: alex-sheih@yandex.ru

A.A. Teplykh – Ph.D.(Phys.-Math.), Senior Research Scientist, 

Saratov branch of Kotel’nikov IRE of RAS

E-mail: teplykhaa@mail.ru

I.A. Borodina – Ph.D.(Phys.-Math.), Leading Research Scientist, 

Saratov branch of Kotel’nikov IRE of RAS

E-mail: borodinaia@yandex.ru