Funding for this research was provided by:
Università degli Studi di Salerno
Text and Data Mining valid from 2018-10-08
Received: 25 July 2018
Accepted: 26 September 2018
First Online: 8 October 2018
Compliance with ethical standards
: The authors declare that they have no conflict of interest. All the authors read and approved the final version of the manuscript.