Thudium, Marcus
Ellerkmann, Richard K.
Heinze, Ingo
Hilbert, Tobias http://orcid.org/0000-0002-2090-8812
Article History
Received: 23 October 2018
Accepted: 25 February 2019
First Online: 9 March 2019
Ethics approval and consent to participate
: This observation was performed after approval by the institutional review board of the University of Bonn (protocol number 300/16, date of approval 2016-06-16). According to the approval, informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.
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