1. Ball, J. N. - 1957 - The biology of the brown trout of Llyn Tegid. Ph. D. Thesis, University of Liverpool.
2. Berg, K. - 1938 - Studies on the bottom animals of Esrom Lake. K. danske vidensk. Selsk. Skr. 9: 1–255.
3. Berg, K. - 1948 - Biological studies on the River Susaa. Folia limnol. scand. 4, 1–318.
4. Berg, K. - 1952 - On the oxygen consumption of Ancylidae (Gastropoda) from an ecological point of view. Hydrobiologia, 4: 225–267.
5. Berg, K. & Peterson, I. C. - 1956 - Studies on the humic acid lake Gribso. Folia limnol. scand. 8: 1–273.