TY  - RPRT
TI  - Annotated orthophoto map, 1970, Washington urban area, D.C., Md. and Va.
AU  - Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey
PY  - 1973
DO  - 10.3133/i858b
UR  - https://pubs.usgs.gov/publication/i858B
ID  - i858B
ER  -