1. Military Academy, University of Defence, Veljka Lukica Kurjaka 33,11042 Belgrade, Serbia
2. Mechanical Engineering Faculty, University of Niš, Aleksandra Medvedeva 14, 18000 Niš, Serbia
3. Department of Structural Analysis, Berlin Institute of Technology, Strasse des 17, Juni 135, 10623 Berlin, Germany
4. Institute of Mechanical Science, Vilnius Gediminas Technical University, 10105 Vilnius, Lithuania