Authors
Sabina Cherneva
Institute of Mechanics, Bulgarian Academy of Sciences, Bulgaria
Vladimir Petrunov
Faculty of Dental Medicine, Medical University of Sofia, Sofia, Bulgaria
Vladimir Petkov
Institute of Metal Science, Equipment and Technologies with Hydro- and Aerodynamics Centre, “Acad. A. Balevski”, Bulgarian Academy of Sciences, Bulgaria
Vladimir Bogdanov
Faculty of Dental Medicine, Medical University of Sofia, Sofia, Bulgaria
Silviya Simeonova
Faculty of Chemistry and Pharmacy, Sofia University, Sofia, Bulgaria