1. Ackery, P.R. and Vane-Wright, R.I. (1984) Milkweed Butterflies. British Museum (Natural History), London.
2. Adamus, P.R. (1983) A method for functional wetland assessment, Vol. 1, Critical review and evaluation concepts; Vol. 11, Assessment methods. Office of research, Development and technology, Federal Highway Administration, US Department of Transportation, Washington, DC.
3. Anselin, A., Meire, P.M. and Anselin, L. (1989) Multicriteria techniques in ecological evaluation: an example using the analytical hierarchy process. Biological Conservation, 49, 215–29.
4. Bardecki, M., Manning, E.W. and Bond, W. (1989) Practical methods for valuing wetlands: an assessment of three approaches, in the Proceedings of the International Symposium on Wetlands and River Corridor Management (eds J.A. Kusler and S. Daly), Berne, New York, USA, pp. 367–71.
5. Bedward, M., Pressey, R.L. and Nicholls, A.O. (1991) Scores and score classes for evaluating criteria: a comparison based on the cost of reserving all natural features. Biological Conservation, 56, 281–94.