Funding for this research was provided by:
Text and Data Mining valid from 2019-01-09
Received: 13 July 2018
Accepted: 2 January 2019
First Online: 9 January 2019
Ethics approval and consent to participate
: Ethics approval was obtained from the ethics commitee of the Technical University of Munich.
: Not applicable.
: The authors declare they have no conflict of interest.
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