TY  - BOOK
AU  - Tolley,H.R.
AU  - Humphries,W.R.
TI  - Tractors and horses in the winter wheat belt,: Oklahoma, Kansas, Nebraska
T2  - United States. Dept. of agriculture
AV  - S711 .T65
PY  - 1924///
CY  - Washington
PB  - Govt. print off.
KW  - Horses
KW  - Traction-engines
N1  - Joint contribution from Bureau of public roads, Bureau of agricultural economics, Bureau of animal industry
ER  -