Text and Data Mining valid from 2019-07-18
Received: 12 October 2018
Accepted: 8 May 2019
First Online: 18 July 2019
Compliance with ethical standards
: The authors declare no conflict of interest, and that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
: This article does not involve any studies conducted on human participants or animals, carried out by any of the authors.