1. In Symposium, Analysis of Carcinogenic Air Pollutants, Nat. Cancer Inst. Monograph No. 9 (edit. by Sawicki, E., and Cassel, K.) (U.S. Government Printing Office, Washington 25, D.C., 1962).
2. Hueper, W. C., Kotin, P., Tabor, E. C., Payne, W. W., Falk, H., and Sawicki, E., Arch. Pathol., 74, 89 (1962).
3. Sawicki, E., Amer. Med. Assoc. Arch. Environ. Hlth. (in the press).
4. Epstein, S. S., J. Air Pollut. Control Assoc., 16, 545 (1966).
5. Epstein, S. S., Small, M., Koplan, J., Mantel, N., Falk, H. L., and Sawicki, E., Amer. Med. Assoc Arch. Environ. Hlth., 7, 531 (1963).