1. I.A. Blakar, and O.J. Jacobsen (1978 ) Zooplankton distribution and abundance in seven lakes from Jotunheimen, a Norwegian high mountain area . Arch. Hydrobiol. (in press).
2. MODIFIED VAN DORN WATER SAMPLER
3. IMPROVED TRIPPING MECHANISM FOR PLASTIC WATER SAMPLERS
4. Large-volume water samplers