TY  - BOOK
AU  - Weed, Clarence M.
AU  - Riley, William E.
TI  - Crop production: an introduction text for schools 
SN  - 9781343184336
PY  - 1914///
CY  - Boston, New York, Chicago
PB  - D. C. Health & Co., Publishers.
KW  - Cropping system
ER  -