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American Agriculture, 1899 - 1939 : A study of output, employment and productivity
Barger, Harold, (1942)
The Agricultural Productivity Gap
Gollin, Douglas, (2013)
The international comparison of value added, productivity and purchasing power parities in agriculture
Maddison, Angus, (1993)
World economic performance : past, present and future : essays in celebration of the life and work of Angus Maddison
Prasada Rao, D. S., (2013)
The International Comparison of Value Added, Productivity and Purchasing Power Parities in Agriculture