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Convergence in US productivity growth for agriculture : implications of interstate research spillovers for funding agricultural research
MacCunn, Alan, (2000)
A nonparametric analysis of the influence of research on agricultural productivity
Chavas, Jean-Paul, (1992)
Theory and econometric analysis of state government demand for public agricultural research
Khanna, Jyoti, (1990)
Supply and demand functions for multiproduct US cash grain farms : biases caused by research and other policies
Huffman, Wallace E., (1989)
Long-run structural and productivity change in US agriculture : effects of prices and policies
Evenson, Robert E., (1997)
Structural and productivity change in US agriculture, 1950 - 1982
Huffman, Wallace E., (2001)