Funding for this research was provided by:
Ministerio de Economía, Industria y Competitividad, Gobierno de España (FFI2016-75249-P)
Text and Data Mining valid from 2019-11-06
Received: 5 June 2019
Accepted: 15 October 2019
First Online: 6 November 2019
Compliance with Ethical Standards
: On behalf of all authors, the corresponding author states that there is no conflict of interest.