Text and Data Mining valid from 2018-09-06
Received: 18 July 2018
Accepted: 29 August 2018
First Online: 6 September 2018
Ethics approval and consent to participate
: The study was performed in accordance with the ethics standards at the Technical University of Munich (TUM) (ethical vote: 06.04.2018s, 90/18 S).Name of committee: Ethikkommission der Technischen Universität München.
: Not applicable.
: The authors declare that they have no competing interests.
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