1. Department of Digital Technologies, Voronezh State University, Universitetskaya sq. 1, 394018 Voronezh, Russia
2. Department of Applied Mathematics and Mechanics, Voronezh State Technical University, XX-Letiya Oktyabrya st. 84, 394006 Voronezh, Russia
3. Geophysical Survey of Russia Academy of Sciences, Lenina av. 189, 249035 Obninsk, Russia