1. Department of Bioresources and Polymer Science, University Politehnica of Bucharest, Bucharest, Romania
2. National Institute for Lasers, Plasma and Radiation Physics, Magurele, Ilfov, Romania
3. SC HOFIGAL SA, 2 Intrarea Serelor, Bucharest, Romania
4. Department of Analytical Chemistry, University of Bucharest, Bucharest, Romania