@misc{indiciae3270b5b7cf7d,
  title = {Geologic map of the Spokane Quadrangle, Washington, Idaho, and Montana},
  author = {A. B. Griggs},
  year = {1973},
  doi = {10.3133/i768},
  url = {https://pubs.usgs.gov/publication/i768},
  note = {Source identifier: i768}
}