Bikchentaev, Airat http://orcid.org/0000-0001-5992-3641
Funding for this research was provided by:
development program of the Scientific and Educational Mathematical Center of the Volga Federal District (075-02-2020-1478)
Article History
Received: 16 March 2021
Accepted: 12 July 2021
First Online: 24 July 2021