Funding for this research was provided by:
Ruprecht-Karls-Universität Heidelberg
Article History
Received: 2 July 2019
Revised: 18 December 2019
Accepted: 20 December 2019
First Online: 27 January 2020
Compliance with ethical standards
:
: The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.
: The authors declare that they have no conflict of interest.