Funding for this research was provided by:
State Scholarships Foundation (MIS 5001552)
Text and Data Mining valid from 2019-11-05
Received: 23 May 2019
Accepted: 23 October 2019
First Online: 5 November 2019
Ethics approval and consent to participate
: The present study was based on analysis on already collected and published data, thus no ethical approval or consent was required.
: Not applicable.
: The authors declare that they have no competing interests.