1. Ames, D. L., Roberts, L. E. and Webb, A. H.: 1987,Atmospheric Environment 21, 1947.
2. Barrie, L. A.: 1978,Atmospheric Environment 12, 407.
3. Bates, R. G.: 1973,Determination of pH: Theory and Practice, John Wiley and Sons, New York.
4. Beverland, I. J., Crowther, J. M. and Srinivas, M. S. N.: 1996. Episodic Deposition of Acid Material at a Site in SE England’, Presented at5th International Conference on Acid Deposition, Gotenberg, Sweden, 26–30th June. Accepted by Water, Air and Soil Pollution.
5. Berverland, I. J. and Crowther, J. M.: 1992,Environmental Pollution 75, 163.