Valkovič, Ladislav
Chmelík, Marek
Ukropcová, Barbara
Heckmann, Thomas
Bogner, Wolfgang
Frollo, Ivan
Tschan, Harald
Krebs, Michael
Bachl, Norbert
Ukropec, Jozef
Trattnig, Siegfried
Krššák, Martin
Article History
Received: 17 August 2015
Accepted: 16 December 2015
First Online: 3 February 2016
Competing interests
: The authors declare no competing financial interests.