1. Calcote, H. F., and King, I. R., Fifth Symposium on Combustion, 423 (Reinhold Publ. Corp., New York, 1955); J. Chem. Phys., 23, 2203 (1955); J. Chem. Phys., 31, 833 (1959).
2. Knewstubb, P. F., and Sugden, T. M., Nature, 181, 1261 (1958). Deckers, J., and Van Tiggelen, A., ibid., 181, 1460 (1958).
3. Hirschler, D. A., McCullough, J. D., and Hall, C. A., Soc. Auto. Eng. Trans., 62, 40 (1954).
4. Loeb, L., Static Electrification (Springer Verlag, Berlin; 1958).
5. Westermark, T., in Symposium on Chemical and Biological Problems related to Smoking, Stockholm, May 1960. Ark. Kemi (in the press); Acta Med. Scand. (in the press).