TY  - GEN
AU  - Torssell, B. W. R.
AU  - Eagerberg, B.
TI  - Predicting economic optimum and nitrogen balance in the ley - ruminant system
SN  - 9157643490
U1  - 338.16 
PY  - 1990///
CY  - Uppasala
PB  - Department of Crop Production Science
KW  - Production efficient
KW  - Agriculture
ER  -