Sokołowski, Wojciech
Barszcz, Karolina
Kupczyńska, Marta
Czubaj, Norbert
Skibniewski, Michał
Purzyc, Halina
Article History
Received: 4 December 2017
Accepted: 18 May 2018
First Online: 27 June 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.