1. Norwegian Institute for Nature Research (NINA); Trondheim Norway
2. Biology Centre of the Czech Academy of Sciences; Institute of Hydrobiology; České Budějovice Czech Republic
3. University of South Bohemia in České Budějovice; Faculty of Science; České Budějovice Czech Republic
4. University of Jyväskylä; Department of Biological and Environmental Science; Jyväskylä Finland