@misc{indiciae21d43bd06c0c,
  title = {Geologic map and distribution of heavy minerals in Tertiary rocks of the Gillette 30' x 60' Quadrangle, Campbell, Crook, and Weston counties, Wyoming},
  author = {N.M. Denson and D. L. Macke and R.R. Schumann},
  year = {1989},
  doi = {10.3133/i2023},
  url = {https://pubs.usgs.gov/publication/i2023},
  note = {Source identifier: i2023}
}