REFERENCES
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- Drenski P. (1951) Fishes in Bulgaria. Bulg. Acad. Sci., Sofia, p. 270 (In Bulgarian).
- Karapetkova M. (1979) XXI Arbeitstagung der IAD Wissenschaftliche Kurzreferate, Novi Sad, SFR Jugoslawien, 378–384.
- Karapetkova M., Dikov. (1986) Hydrobiology 28, 3–14 (In Bulgarian, English summary).
- Kottelat M., Freyhof J. (2007) Handbook of European Freshwater Fishes, p. 646
- Kovachev V. (1923) Freshwater ichthyofauna in Bulgaria. Archive of the Ministry of the agriculture and state property, Sofia, p. 142 (In Bulgarian).
- Shishkov G. (1937) Fishing review, 7, No 5, 66–68 (In Bulgarian).
- Vassilev M., Pehlivanov L. (2005) Acta zool. Bulg., 57(2), 161–190.