10BalI,V. E. ,Rolf Fare, Shawna Grosskopf, and Richard Nehring. 2001. "Productivity of the U. S. Agricultural Sector:The Case of Undesirable Outputs. " In New Developments in Productivity Analysis, ed. C. R. Hulten, E. Dean and M. J. Harper, 541 -585. Chicago, U. S. A. : University of Chicago Press.
