@misc{indiciae0a9d329a6032,
  title = {Bedrock and surficial engineering geologic maps of the Littleton Quadrangle, Jefferson, Douglas, and Arapahoe counties, Colorado},
  author = {Edward E. McGregor and John T. McDonough},
  year = {1980},
  doi = {10.3133/ofr80321},
  url = {https://pubs.usgs.gov/publication/ofr80321},
  note = {Source identifier: ofr80321}
}