Text and Data Mining valid from 2019-02-11
Received: 24 July 2018
Accepted: 29 January 2019
First Online: 11 February 2019
Ethics approval and consent to participate
: The study was approved by Regional Ethical Committee for Science: PTE KK 6383 University of Pécs. Written informed consents were obtained from all the participants.
: Not applicable.
: The authors declare that they have no competing interests.
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