TY  - RPRT
TI  - Resources for the 21st century; summary and conclusions of the International Centennial Symposium of the U.S. Geological Survey
AU  - Frank C. Whitmore
PY  - 1981
DO  - 10.3133/cir857
UR  - https://pubs.usgs.gov/publication/cir857
ID  - cir857
ER  -