TY  - RPRT
TI  - Energy resources of the United States
AU  - P. K. Theobald
AU  - Stanley P. Schweinfurth
AU  - Donald Cave Duncan
PY  - 1972
DO  - 10.3133/cir650
UR  - https://pubs.usgs.gov/publication/cir650
ID  - cir650
ER  -