TY  - RPRT
TI  - Colored gravity anomaly and terrain maps of the east-central United States
AU  - Robert W. Simpson
AU  - Richard H. Godson
PY  - 1981
DO  - 10.3133/ofr81846
UR  - https://pubs.usgs.gov/publication/ofr81846
ID  - ofr81846
ER  -