References
- Brinkhurst, R. O. & Jamieson, B. G. M., 1971: Aquatic oligochaeta of the World. — Oliver & Boyd, 860 pp.
- Milbrink, G., 1973 a: On the Use of Indicator Communities of Tubificidae and some Lumbriculidae in the Assessment of Water Pollution in Swedish Lakes. — ZOON 1: 125–139.
- Milbrink, G., 1973 b: Communities of Oligochaeta as Indicators of the Water Quality in Lake Hjälmaren. — ZOON 1: 77–88.
- Ryder, R. A., Kerr, S. R., Loftus, K. H. & Regier, H. A., 1974: The Morphoedaphic Index, a Fish Yield Estimator Review and Evaluation. — J. Fish. Res. Board. Can. 31 (5): 663–688.
- Wiederholm, T., 1973: ottenfaunaundersökningar i Vänern, maj 1973. — SNV PM 39, Statens Naturvårdsverk (in Swedish).
- Wiederholm, T. 1974: Studier av bottenfaunan i Mälaren. — SNV PM 415, Statens Naturvårdsverk (in Swedish).
- Wiederholm, T. 1976: Chironomids as indicators of water quality in Swedish lakes. — NLU Information 10, Naturvårdsverkets Limn. Undersökning.
- Wiederholm, T. 1977: Bottenfaunan i Hjälmaren. — SNV PM 820, Statens Naturvårdsverk (in Swedish).