TY  - RPRT
TI  - Mineral resources of the United States, 1920: Part II - Nonmetals
AU  - Gerald Francis Loughlin
AU  - Ralph Walter Stone
PY  - 1923
DO  - 10.3133/70175844
UR  - https://pubs.usgs.gov/publication/70175844
ID  - 70175844
ER  -