1. An Economic Analysis of Field Crop Production, Insecticide Use, and Soil Erosion in a Subbasin of the Iowa River;Alt,1976
2. Pest Management Guides;Cooperative Extension Service, Virginia Polytechnic Institute and State University,1977
3. Insecticide requirements in an efficient agricultural sector;Dixon;Rev. Econom. Statist.,1973
4. A Linear Programming Model of Diary Farm Nutrient Management;Haith,1977
5. Effectiveness of Soil and Water Conservation Practices for Pollution Control,1979