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Economic evaluation of investment in soil conservation by farm households in Hararghe Highlands of Ethiopia
Adenew, Berhanu, (2001)
Comparative economics of alternative agricultural production systems : a review
Fox, Glenn, (1991)
Risk analysis of tillage alternatives with government programs
Williams, Jeffery R., (1990)
Conservation of plant genetic resources for food and agriculture : main actors and the costs to bear
Virchow, Detlef, (1999)
Spending on conservation of plant genetic resources for food and agriculture : how much and how efficient?
Die Erhaltung der Agrobiodiversität
Virchow, Detlef, (2008)