Funding for this research was provided by:
FundaICcão para a Ciência e a Tecnologia (UID/MAT/00324/2019, SAICTPAC/0011/2015)
FundaICcão para a Ciência e a Tecnologia (PD/BD/128060/2016)
Article History
Received: 25 July 2018
Accepted: 25 November 2019
First Online: 3 December 2019