1. BENGTSON, S. A., and A. SODERGREN: Ambio3, 84 (1974).
2. BIDLEMAN, T. F., J. R. MATTHEWS, C. E. OLNEY, and C. P. RICE: J. Assoc. Offic. Anal. Chem.61, 820 (1978).
3. CHAU, A. S. Y. and W. P. COCHRANE: J. Assoc. Offic. Anal. Chem.52, 1092 (1969).
4. HEESEN, T. C. and R. A. JOHNSON: Southern California Coastal Water Research Project, Annual Report, 39 (1976).
5. McCLURE, V. E.: Environ. Sci. Technol.10, 1223 (1976).