3Graham - Tomasi(1991), "Sustainability: Concepts and Applications for Agricultural Research Policy," The Hague: The Hague:Services for National Agricultural Research.
4Hayami and Ruttan (1985)."Agricultural Development: An International Perspective." The Johns Hopkins University Press, Baltimore, USA.
6P. Pardey, J. Roseboom and J. Anderson, eds. (1991), Agricultural research Policy: International Quantitative Perspectives (The Hague:Services for National Agricultural Research).
