Funding for this research was provided by:
Narodowe Centrum Nauki (No N N403 2424 40)
Text and Data Mining valid from 2018-12-18
Received: 21 June 2018
Accepted: 4 December 2018
First Online: 18 December 2018
Compliance with ethical standards
: The authors declare no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.