TY  - RPRT
TI  - Map showing potential sources of gravel and crushed-rock aggregate in the Boulder-Fort Collins-Greeley area, Front Range urban corridor, Colorado
AU  - R. B. Colton
AU  - H. R. Fitch
PY  - 1974
DO  - 10.3133/i855d
UR  - https://pubs.usgs.gov/publication/i855D
ID  - i855D
ER  -