1. Research Hydraulic Engineer, U.S. Water Conservation Laboratory, USDA/ARS, 4331 E. Broadway Rd., Phoenix, AZ 85040.
2. Director, U.S. Water Conservation Laboratory, USDA/ARS, 4331 E. Broadway Rd., Phoenix, AZ 85040.
3. Electrical Engineer, U.S. Water Conservation Laboratory, USDA/ARS, 4331 E. Broadway Rd., Phoenix, AZ 85040.