Text and Data Mining valid from 2019-04-06
Received: 6 December 2018
Accepted: 29 March 2019
First Online: 6 April 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interests.
: This article does not contain any studies with human participants or animals performed by any of the authors.
: For this type of study format, consent was not required.