References
- Edmondson, W. T. & Winberg, G. G., 1971: A manual on methods for the assessment of secondary productivity in freshwaters. — I.B.P. Handbook 17: 1–358.
- Golterman, H. L. & Clymo, R. S., 1969: Methods for chemical analysis of freshwaters. —I.B.P. Handbook 8: 1–166.
- Michael, J. T., Greenberg, A. E., Hoak, R. D. & Rand, M. C., 1971: Standard methods for the examination of water and wastewater. —Amer. Public Health Assoc., Washington, D.C., 874 pp.
- Vollenweider, R. A., Talling, J. F. & Westlake, D. F., 1974: A manual on mehtods for measuring primary production in aquatic environments. — I.B.P. Handbook 12: 1–225.