Text and Data Mining valid from 2019-03-22
Received: 22 November 2018
Accepted: 18 March 2019
First Online: 22 March 2019
Compliance with ethical standards
: On behalf of all authors, the corresponding author states that there is no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.
: Informed consent was obtained from all individual participants included in the study.