Article History
Received: 1 August 2018
Accepted: 1 November 2018
First Online: 14 November 2018
Compliance with ethical standards
:
: M. Cieślak declares that he/she has no conflict of interest.K. Roszek declares that he/she has no conflict of interest.M. Wujak declares that he/she has no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.