TY  - RPRT
TI  - Surficial geologic map of parts of Billerica, Wilmington, and Lexington quadrangles, Massachusetts
AU  - Robert O. Castle
PY  - 1950
DO  - 10.3133/ofr5031
UR  - https://pubs.usgs.gov/publication/ofr5031
ID  - ofr5031
ER  -