1. Department of Analytical and Physical Chemistry, University of Food Technologies, 26 Maritza Blvd., 4002 Plovdiv, Bulgaria
2. Department of Chemical Technology, University of Plovdiv “Paisii Hilendarski”, 24 Tzar Asen Str., 4000 Plovdiv, Bulgaria
3. Department Technology of Tobacco, Sugar, Vegetable and Essential Oils, University of Food Technologies, 26 Maritza Blvd., 4002 Plovdiv, Bulgaria