Gilbert, J. (1895). Agricultural investigation at Rothamsted, England during a period of fifty years: научное издание.
Chicago-viite (17. p.)Gilbert, J.H. Agricultural Investigation at Rothamsted, England During a Period of Fifty Years: научное издание. 1895.
MLA-viite (9. p.)Gilbert, J.H. Agricultural Investigation at Rothamsted, England During a Period of Fifty Years: научное издание. 1895.
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