TY  - RPRT
TI  - One hundred and sixty years of Grand Canyon geological mapping
AU  - Karl Karlstrom
AU  - Laura Crossey
AU  - Peter W. Huntoon
AU  - George Billingsley
AU  - Michael Timmons
AU  - Ryan S. Crow
PY  - 2019
UR  - https://pubs.usgs.gov/publication/70212617
ID  - 70212617
ER  -