1. Hydrologist, Office of Surface Water, U.S. Geological Survey, 9818 Bluegrass Pkwy., Louisville, KY 40299.
2. Graduate Student, Ven Te Chow Hydrosystems Laboratory, Univ. of Illinois, 205 N. Mathews, Urbana, IL 61801.
3. Professor, Instituto Superior de Recursos Hídricos, Universidad Nacional de Córdoba. Av. Filloy s/n. Ciudad Universitaria, Córdoba, Argentina.
4. Oceanographer, National Research Program, U.S. Geological Survey, 520 N. Park Ave., Tucson, AZ 85719.
5. Chester and Helen Siess Professor, and Director, Ven Te Chow Hydrosystems Laboratory, Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana-Champaign, 205 North Mathews Ave., Urbana, IL 61801.