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1928 : by C. Burgess. With some observations by G. Ll. Rogers
Burgess, C., (1929)
Four yearʹs farming in East Anglia, 1923-1927 : being a detailed investigation of the costs and returns on twenty-six farms
Carslaw, R. McG., (1929)
Agriculture and the state : the financial and economic results of control
Venn, John Archibald, (1939)