1. Beckett, D. C.: Ordination of macroinvertebrate communities in a multistressed river system, In J. H. Thorp and J. W. Gibbons (eds.): Energy and environmental stress in aquatic systems. p. 748. Technical Information Center, U.S. Department of Energy, Springfield, VA. (1978).
2. Bormann, F. H., and G. E. Likens: Pattern and process in a forested ecosystem, New York: Springer-Verlag (1979).
3. Bradt, P. T.: Longitudinal variation in the macroinvertebrate fauna and water chemistry of an eastern Pennsylvania trout stream, In J. H. Thorp and J. W. Gibbons (eds.): Energy and environmental stress in aquatic systems, p. 771. Technical Information Center, U.S. Department of Energy, Springfield, VA. (1978).
4. Brender, E. V.: Silviculture of loblolly pine in the Georgia Piedmont. Ga. For. Res. Counc. Rep.33, 74 (1973).
5. Burlington, R. F.: Quantitative biological assessment of pollution, J. Water Pollut. Control Fed.,34, 414 (1962).