TY  - RPRT
TI  - Preliminary report on aggregate use and permitting along the Colorado Front Range
AU  - David R. Wilburn
AU  - William H. Langer
PY  - 2000
DO  - 10.3133/ofr00258
UR  - https://pubs.usgs.gov/publication/ofr00258
ID  - ofr00258
ER  -