TY  - RPRT
TI  - Borehole gravity surveys of the U.S. Geological Survey (1963-1975); brief history and basic data
AU  - L. A. Beyer
PY  - 1980
DO  - 10.3133/ofr80903
UR  - https://pubs.usgs.gov/publication/ofr80903
ID  - ofr80903
ER  -