Funding for this research was provided by:
Ministry of Education and Science of the Russian Federation (5–100 program of the Russian Ministry of Education (5-100)
Gruppo Nazionale per l’Analisi Matematica, la Probabilità e le loro Applicazioni (2019)
Article History
Received: 16 April 2020
Accepted: 8 September 2020
First Online: 21 September 2020