1. Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy;Off. J.,2000
2. Hydrobiological studies of the Maritsa River. I;Rusev,1966
3. Hydrobiological studies of the Maritsa River. II;Rusev,1967
4. Hygienic Characteristics of the Catchment Area of the Maritsa River;Efremov;NISHI,1968
5. Tendencies of the changes in the saprobic condition of the Maritsa River;Rusev;Hydrobiology,1981