TY  - BOOK
AU  - Osborn,W.M.
AU  - Mathews,O.R.
TI  - Crop rotation tillage and fertility experiments at the Lawton(okla) field station, 1917-49
U1  - 633 
PY  - 1955///
CY  - Washington
PB  - U.S. Dept. of Agriculture.
ER  -