1. Barrett, C.F. et al, 1988. Acid deposition in the United Kingdom 1981–1985. UK Review Group on Acid Rain 2nd report. Department of the Environment. London.
2. Bull, K.R., 1991. The Critical Loads/Levels Approach to gaseous pollutant emission control. Envir. Pollution, 69: 105–123.
3. Derwent R.G., et al, 1988. Ozone in the United Kingdom. United Kingdom Photochemical Oxidants Review Group Interim Report. Department of the Environment, London.
4. Finney, D.J., 1971. Probit Analysis. Cambridge University Press, London.
5. Murlis, J. and Jones, C.D., 1981. Fine-scale structure of odour plumes in relation to insect orientation to distant pheromone and other attractant sources. Physiol. Entomol., 6: 71-.