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Land tenure and the adoption of conservation practices
Soule, Meredith J., (2000)
Honorierung ökologischer Leistungen - Erfahrungen mit dem US-amerikanischen "Conservation Reserve Program" (CRP)
Plankl, Reiner, (1999)
Energy and the use of conservation tillage in US agriculture
Uri, Noel Dean, (1999)
Yield-topsoil depth response functions : linear versus Mitscherlich-Spillman
Hoag, Dana L., (1983)
Agricultural crisis in America : a reference handbook
Hoag, Dana L., (1999)
Economic principles for saving the cooperative extension service
Hoag, Dana L., (2005)