Czyszanowski, Tomasz
Gebski, Marcin
Dems, Maciej
Wasiak, Michał
Sarzała, Robert
Panajotov, Krassimir
Article History
Received: 27 October 2016
Accepted: 5 December 2016
First Online: 12 January 2017
Competing interests
: The authors declare no competing financial interests.