1. Conn, W.D. and Rich, R.C. (1992) Communicating about ecosystem risks. In Predicting Ecosystem Risk J.CairnsJr., B.R.Niederlehner and D.R.Orvos (eds), pp. 1–8. Princeton: Princeton Scientific Publishing.
2. Costanza, R., Daly, H.E. and Bartholomew, J.A. (1991) Goals, agenda and policy recommendations for ecological economics. In Ecological Economics: The Science and Management of Sustainability R.Costanza (ed.), pp. 1–21. New York: Columbia University Press.
3. Hunsaker, C.T., Graham, R.L., Suter, G.W.II, O'Neill, R.V., Barnthouse, L.W. and Gardner, R.H. (1990) Assessing ecological risk on a regional scale. Environ. Manag.
14, 325–32.
4. Likens, G.E., ed. (1989) Long Term Studies in Ecology: Approaches and Alternatives. New York: Springer-Verlag.
5. Risser, P.M., ed. (1991) Long-term Ecological Research: An International Perspective, SCOPE, vol. 47. New York: Wiley.