1. Junge, C. E., Air Chemistry and Radioactivity, 37 (Academic Press, New York and London, 1963).
2. Air Quality Data from the National Air Sampling Networks, 1964—1965 (US Department of Health, Education and Welfare, 1966).
3. Wisse, J. A., and Velds, C. A., Atmos. Environ., 4, 79 (1970).
4. Cadle, R. D., in Air Pollution Handbook (edit. by Magill, P. L., Holden, F. R., and Ackley, C.), 3 (McGraw-Hill, New York, 1956).
5. Leighton, P. A., Photochemistry of Air Pollution, 159 (Academic Press, New York, 1961).