Pretty, J. N. (1988). Preference ranking. Northeast Rainfed Agricultural Development (NERAD) Project, Northeast Regional Office of Agriculture.
Chicago-viite (17. p.)Pretty, Jules N. Preference Ranking. Khon Kaen, Thailand: Northeast Rainfed Agricultural Development (NERAD) Project, Northeast Regional Office of Agriculture, 1988.
MLA-viite (9. p.)Pretty, Jules N. Preference Ranking. Northeast Rainfed Agricultural Development (NERAD) Project, Northeast Regional Office of Agriculture, 1988.
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