Funding for this research was provided by:
Ministerio de Economía, Industria y Competitividad, Gobierno de España (Project AGL2014-51964-C2-2-R)
Text and Data Mining valid from 2018-09-18
Received: 19 June 2018
Accepted: 10 September 2018
First Online: 18 September 2018
Compliance with ethical standards
: The authors declare that they have no conflict of interest.