Text and Data Mining valid from 2018-10-11
Received: 5 June 2018
Accepted: 28 September 2018
First Online: 11 October 2018
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.
: For this type of study informed consent is not required.
: For this type of study consent for publication is not required.