TY  - RPRT
TI  - Agroecosystems, nitrogen-use efficiency, and nitrogen management.
AU  - Kenneth G Cassman
AU  - Achim Dobermann
AU  - Daniel T Walters
PY  - 2002
DO  - 10.1579/0044-7447-31.2.132
UR  - https://pubmed.ncbi.nlm.nih.gov/12078002/
ID  - 12078002
ER  -