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2. Soil and Water Conservation Inf. Bureau, Dep. Land Resour. Sci., 1991. Univ. Guelph, Guelph, ON. Canada N1G 2W1. Personal communication.
3. Effects of Residue Cover on Pesticide Losses from Conventional and No-Tillage Systems
4. Statistical Analysis System, SAS Institute Inc., Cary, NC 27511.