Text and Data Mining valid from 2019-12-09
Received: 5 September 2019
Accepted: 14 November 2019
First Online: 9 December 2019
Compliance with Ethical Standards
: The authors declare that they have no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.
: As no human participants are involved in this study no informed consent had been obtained.