TY  - RPRT
TI  - Phosphate rock demand into the next century: Impact on wolld food supply
AU  - J. R. Herring
AU  - R.J. Fantel
PY  - 1993
DO  - 10.1007/bf02257917
UR  - https://pubs.usgs.gov/publication/70017383
ID  - 70017383
ER  -