Olmstead, A. L., & Rhode, P. W. (2000). The diffusion of the tractor in American agriculture: 1910-60. National Bureau of Economic Research.
Chicago Style aipamenaOlmstead, Alan L., and Paul Webb Rhode. The Diffusion of the Tractor in American Agriculture: 1910-60. Cambridge: National Bureau of Economic Research, 2000.
MLA aipamenaOlmstead, Alan L., and Paul Webb Rhode. The Diffusion of the Tractor in American Agriculture: 1910-60. National Bureau of Economic Research, 2000.
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