References
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- Ilmavirta, V., 1974 a: Electronic particle counting applied in phytoplankton studies in three southern Finnish lakes. — Ann. Bot. Fennici 11: 105–111.
- Ilmavirta, V., 1974 b: Diel periodicity in the phytoplankton community of the oligotrophic lake Pääjärvi, southern Finland. I. Phytoplanktonic primary production and related factors. — Ann. Bot. Fennici 11: 121–132.
- Ilmavirta, V., 1974 c: Notes on the effect of the filtration process on measurements of phytoplanktonic primary production in Lake Pääjärvi, southern Finland. — Ann. Bot. Fennici 11: 250–252.
- Ilmavirta, V., 1977: Diel periodicity in the phytoplankton community of the oligotrophic lake Pääjärvi, southern Finland. III. The effects of bottle material on production. — — Ann. Bot. Fennici 14: 102–111.
- Ilmavirta, V., Ilmavirta, K. & Kotimaa, A.-L., 1974: Phytoplanktonic primary production during the summer stagnation in the eutrophicated lakes Lovojärvi and Ormajärvi, southern Finland. — Ann. Bot. Fennici 11: 121–132.
- Jones, R. I. & Ilmavirta, V., 1978: A diumal study of the phytoplankton in the eutrophic lake Lovojärvi, southern Finland. — Arch. Hydrobiol. 83: 494–514
- Keskitalo, J., 1977: The species composition and biomass of phytoplankton in the eutrophic Lake Lovojärvi, southern Finland. — Ann. Bot. Fennici 14: 71–81.
- Ruuhijärvi, R., 1974: A general description of the oligotrophic lake Pääjärvi, southern Finland, and the ecological studies on it. — Ann. Bot. Fennici 11: 95–104.