O.V. Betskii – Dr. Sc. (Phys.-Math.), Professor (1938–2020)

L.A. Morozova – Research Scientist, 

Fryazino Branch of the Institute of Radio Engineering and Electronics n.a. V.A. Kotelnikov of RAS (Fryazino, Moscow Region)

E-mail: mila-morozova.ludmila@yandex.ru

S.V. Savel’ev – Ph.D. (Phis.-Math.), Leading Research Scientist, 

Fryazino Branch of the Institute of Radio Engineering and Electronics n.a. V.A. Kotelnikov of RAS (Fryazino, Moscow Region)

E-mail: savelyev@ms.ire.rssi.ru