Text and Data Mining valid from 2018-12-01
Received: 29 August 2018
Accepted: 19 November 2018
First Online: 3 December 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: 21.06.2018, 266/18 S).Name of committee: Ethikkommission der Technischen Universität München.
: Not applicable.
: The authors declare that they have no competing interests.
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