@misc{indiciae982dcc6a7c5d,
  title = {Geology and mineral resources of the Aniakchak district},
  author = {R. S. Knappen},
  year = {1929},
  doi = {10.3133/b797f},
  url = {https://pubs.usgs.gov/publication/b797F},
  note = {Source identifier: b797F}
}