Funding for this research was provided by:
Ministry of SCience and Higher EDucation, POland (MSHE DIR/WK//2016/05, MSHE 220815/E-383/SPUB/2016/2)
Text and Data Mining valid from 2019-11-26
Received: 21 December 2018
Accepted: 28 October 2019
First Online: 26 November 2019
Compliance with ethical standards
: On behalf of all authors, the corresponding author states that there is no conflict of interest.