1. Gianessi, L. P.; Puffer, C. M. Resources for the Future; Herbicide Use in the United States-National Summary Report, revised April 1991; Washington, DC, 1990; 128 p.
2. USDA. Agricultural Chemical Usage 1992 Field Crops Summary.
3. USDA. Agricultural Chemical Usage 1993 Field Crops Summary.
4. Evaluation of Pesticide Groundwater Pollution Potential from Standard Indices of Soil-Chemical Adsorption and Biodegradation
5. Goolsby, D. A.; Thurman, E. M.; Kolpin, D. W. U.S. Geological Survey Water-Resources Investigations Report 91-4034; 1990; p 183.