TY  - RPRT
TI  - Letters sent by the United States Geological Survey, 1879-1895
AU  - Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey
PY  - 1949
DO  - 10.3133/1480
UR  - https://pubs.usgs.gov/publication/1480
ID  - 1480
ER  -