1. Ioan Ursu Institute of the Faculty of Physics, Babeş-Bolyai University, 1 Kogălniceanu, 400084 Cluj-Napoca, Romania
2. RDI Institute in Applied Natural Sciences, 30 Fântânele, 400327 Cluj-Napoca, Romania
3. Department of Geology, Babeş-Bolyai University, 1 Kogălniceanu, 400084 Cluj-Napoca, Romania
4. Electron Microscopy Center, Department of Experimental Biology, Babeş-Bolyai University, Clinicilor 5, 400006 Cluj-Napoca, Romania