1. Faculty of Mechanics and Mathematics, Lomonosov Moscow State University, GSP-1, 1 Leninskiye Gory, Main Building, Moscow 119991, Russia
2. Fidesys LLC, Office 402, 1 Building 77, MSU Science Park, Leninskie Gory, Moscow 119234, Russia
3. Tver State University, 33 Zhelyabov Street, Tver 170100, Russia