B. A. Tomkins, G. A. Sega, and C-h. B. A. Tomkins, Gary A. Sega, and C-h. U. S. Environmental Protection Agency, Office Water, document no. Slide presentation pp.
Text given on accompanying floppy disk, document no.
W. H. Griest, R. S. Ramsey, C-h. W. H. Griest, R. S. Ramsey, C-h. B. A. Tomkins, Gary A. Sega, and C-h. B. A. Tomkins, Gary A. Sega, and C-h.