TY  - RPRT
TI  - Preliminary geologic map of the Las Trampas Ridge Quadrangle, Contra Costa and Alameda counties, California
AU  - T. W. Dibblee
PY  - 1980
DO  - 10.3133/ofr80545
UR  - https://pubs.usgs.gov/publication/ofr80545
ID  - ofr80545
ER  -