TY  - RPRT
TI  - Cartographic and digital standard for geologic map information, Part C: Principles, content, symbols, colors, patterns, and codes
AU  - Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey
PY  - 1995
DO  - 10.3133/ofr95525c
UR  - https://pubs.usgs.gov/publication/ofr95525C
ID  - ofr95525C
ER  -