1. Ahlgren, G., 1977. Growth of Oscillatoria agardhii in chemostat culture 1. Nitrogen and phosphorous requirements. Oikos 29: 209–224.
2. Beattie, D. M., Bromley, H. J., Chambers, M. R., Goldspink, R., Vijverberg, J., Van Zalinge, N. P. & Golterman, H. L., 1970. Limnological studies on Tjeukemeer — a typical Dutch polder reservoir. Proc. I.B.P.-Unesco Symposium on Productivity Problems of Freshwaters (Kajak, Z. & Hillbricht-Illkowska, A., eds.), pp. 421–447. Kazimierz Dolny, Poland.
3. Beattie, D. M., Golterman, H. L. & Vijverberg, J., 1978. An introduction to the limnology of the Friesian lakes. Hydrobiologia 58: 49–64.
4. Collins, P. F., Diehl, H. & Smith, G. F., 1959. 2,4,6-Tipyridyl-s-triazine as a reagent for iron. Determination of iron in limestone, silicates and refractories. Analyt. Chem. 31: 1862–1867.
5. De Haan, H., 1972. Some structural and ecological studies on soluble humic compounds from Tjeukemeer. Verh. int. Ver. Limnol. 18: 685–695.