Grosso, G
Stepaniak, U
Polak, M
Micek, A
Topor-Madry, R
Stefler, D
Szafraniec, K
Pajak, A
Article History
Received: 17 October 2014
Revised: 8 May 2015
Accepted: 11 June 2015
First Online: 29 July 2015
Competing interests
: The authors declare no conflict of interest.