1. Agricultural Resources of the World,1954
2. Final Report, Sources of Nitrogen and Phosphorus in Water;American Water Works Association Task Group 2610P;J. Am. Wat. Wks. Ass.,1967
3. The Effects of Nitrogen Removal on the Algal Growth Potential of San Joaquin Valley Agricultural Tile Drainage Effluents;Brown,1969
4. California Crop and Livestock Reporting Service.