TY  - RPRT
TI  - Mineral resources of the Appalachian region
AU  - Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey
AU  - U.S. Bureau of Mines
PY  - 1968
DO  - 10.3133/pp580
UR  - https://pubs.usgs.gov/publication/pp580
ID  - pp580
ER  -