TY  - RPRT
TI  - Map showing relative excavatability of geologic materials in the Parker quadrangle, Arapahoe and Douglas Counties, Colorado
AU  - J. O. Maberry
PY  - 1972
DO  - 10.3133/i770h
UR  - https://pubs.usgs.gov/publication/i770H
ID  - i770H
ER  -