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3Edwin Young, Victor Oliveira, Roger Claassen. 2008 Farm Act: Where Will the Money Go [R]. USDA, ERS. :2008.
4Roger Claassen. Emphasis Shifts in U.S. Conservation Policy [R] .USDA, ERS. 2006.
5Roger Claassen, Vince Breneman, Shawn Bucholtz, Andrea Cattaneo, Robert Johansson, and Mitch Morchart. Environmental Compliance in U.S. Agricultural Policy: Past Performance and Future Potential[R]. USDA, ERS. 2004.
