Nguyen, Quoc Tuan http://orcid.org/0000-0002-4794-2762
Funding for this research was provided by:
International Centre for Research and Postgraduate Training in mathematics, Institute of Mathematics, VAST (ICRTM01-2021.01)
Article History
Received: 25 March 2022
Accepted: 11 April 2023
First Online: 4 May 2023