TY  - BOOK
AU  - Martin, John H.
AU  - Leonard, Warren H.
TI  - Principles of Field Crop Production
U1  - 633 
PY  - 1970///
CY  - New York
PB  - Macmillan Co.
KW  - Agriculture and related technologies
KW  - Technology (Applied sciences)
KW  - Field crops
ER  -