Funding for this research was provided by:
Fundação para a Ciência e a Tecnologia (SFRH/BD/93443/2013, SFRH/BD/95438/2013, NORTE-01-0145-FEDER-024300, NORTE-01-0145-FEDER-000013, POCI-01-0145-FEDER-007038)
Text and Data Mining valid from 2019-01-30
Received: 14 September 2018
Accepted: 8 January 2019
First Online: 30 January 2019
Compliance with ethical standards
: The authors declare no conflict of interest.