QSGravCos N O D E S University of Belgrade, Faculty of Physics (UniBgFF) Group for Gravitation, Particles and Fields Contact person: prof. dr Marija Dimitrijević Ćirić email: dmarija@ipb.ac.rs University of Niš (UNI), Faculty of Sciences and Mathematics Physics department Contact person: prof. dr Goran Djorjdević email: gorandj@junis.ni.ac.rs Sofia University “St. Kliment Ohridski” (SUKO) Department of Theoretical Physics Contact person: prof. dr Cvetan Vetsov email: vetsov@phys.uni-sofia.bg University of Craiova, Department of Physics (UCV) Contact person: prof. dr Radu Constantinescu email: rconsta@central.ucv.ro University of Zagreb, Faculty of Science, Department of Physics (UZG), Particles and Fields Contact person: prof. dr Ivica Smolić email: ismolic@phy.hr University of Wroclaw, Institute of Theoretical Physics (UniWIOP) Contact person: prof. dr Andrzej Borowiec email: andrzej.borowiec@uwr.edu.pl University of Banja Luka, Faculty of Natural Sciences and Mathematics Contact person: dr Nemanja Rakić email: nemanja.rakic@pmf.unibl.org Comenius University Bratislava, Faculty of Mathematics, Physics and Informatics (FMPH) Contact person: dr Juraj Tekel email: juraj.tekel@fmph.uniba.sk