1. Reiter, R.: On the Causal Relation Between Nitrogen-Oxygen Compounds in the Troposphere and Atmospheric Electricity. Tellus, XXII, 122, (1970)
2. World Meteorological Organization: Air Pollution Measurement Techniques. Special Environmental Report No. 10, WMO-No. 460, (1977)
3. Georgii, H.W.: World Meteorological Organization, Environmental Pollution Monitoring Program (1982)
4. Pack, D.H. and Shepherd, A.A.: Proceedings; Advisory Workshop on methods for comparing precipitation chemistry data. UAPSP-100 Workshop Proceedings, New York (1982)
5. Department of Energy: Acid Precipitation, a Bibliography. DOE/TIC 3399 (DE83008750), (1983)