Hening, Alexandru
Tran, Ky Quan
Phan, Tien Trong
Yin, George
Funding for this research was provided by:
National Foundation for Science and Technology Development (101.03-2017.23)
Division of Mathematical Sciences (1710827)
Article History
Received: 12 October 2018
Revised: 21 March 2019
First Online: 27 April 2019