1. Department of Physics, Kaunas University of Technology, Studentų Str. 50, LT-51368 Kaunas, Lithuania
2. Laboratory of Biodeterioration Research, Institute of Botany, Nature Research Centre, Akademijos Str. 2, LT-08412 Vilnius, Lithuania
3. Faculty of Physics and Technology, University of Plovdiv “Paisii Hilendarski”, Tzar Assen Str. 24, 4000 Plovdiv, Bulgaria