Schultz, Theodore W.
Economic crises in world agriculture/Theodore W. Schultz
The Minchigan of Univ. Press, 1966
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Snedecor, George W.
Statistical methods, applied, to experiment in agriculture and biology
The Iowa State University Press, 1962
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Schultz, Theodore W.
Agriculture in an ucstable economy / Theodore W. Schultz
McGraw-Hill , 1945
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Mead, R.
Statistical methods in agriculture and experimental biology
Chapman & Hall, 1993
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Ramulu, U.S. Sree
Isotopes in agriculture / U. S. Sree Ramulu
Oxford & IBH Publishing Co., 1982
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