TY  - RPRT
TI  - Preliminary map showing Quaternary deposits and their dating potential in the conterminous United States
AU  - S. M. Colman
AU  - K. L. Pierce
PY  - 1979
DO  - 10.3133/mf1052
UR  - https://pubs.usgs.gov/publication/mf1052
ID  - mf1052
ER  -