Некоторые вопросы экономики производства кукурузы в США

61. Harvesting Corn for Grain, by В ro d e ll and Wa l k e r , Bulletin 129, June 1953. Progressive Farmer, March 1956. ' 64. Gains in Productivity of Farm Labor, by H e c h t and P. T. B a r t o n , Technical Bulletin No 1020, December 1950. Agricultural Situation. Vol. 40, 1956. 65. Implement and Tractor, October 1955, Successful Farming, 1956, 1—12. 66. Changes in Technology and Labor Requirements in Crop Pro* duction Corn, by L. M a c y, L. E. A r n o l d and E. G. M с к i b- ben, June 1938, Work Progress Administration National Research Project. 67. 69, 71. Labor Power and Machinery in Corn Production, by C. S h e d d, E. С о 11 i n s and D a v i d s o n , Bulletin No 365, 1937. Farm Management, 1956. 68. Crop Production Practices. Labor Power and Materials by Ope­ ration, FM 92, Section 2, 3. Northeast, Corn Belt and Lake States, Appalachian, Southeast and Mississippi Delta. Great Plains. 70, 72. Changes in Farm Production and Efficiency. USDA, AES, June 1955. Farm Machinery and Equipment, by H. P. S mi t h , Prof.4 1955. Farm Implement News, 1956, September 10. 73. The Farm Quarterly Summary, 1956, 1957. Farmer Digest, 1956. 75. Iowa Farm Science, April 1957. 74, 76. Farm Implement News, 1956 и 1957, September 10. 77, Farm Machinery and Equipment, by S mi t h , 1955. 78, 81. Cost and Labor used in Harvesting Grain, Storer. Penn. AES, Bulletin No 486. Agricultural Engineering, 1940, November; 1942, April; 1953, Sep­ tember; 1955, December; 1956, February. Cost Production in Texas, AES, No 746, 1952. Corn Picker Operation to Save Corn and Handes, AES Circular No 697, 1952, Illinois. Labor Power and Machinery. The Farm Quarterly, Spring 1956. 79, 80. Farmer Digest, 1956. Successful Farming 1956. Prairie Farmer 1956, June, September. The Farm Quarterly, Summer 1957, Vol. 12, No 2. Farm Management 1957. Электронная Научная Сельскохозяйственная Библиотека