@misc{indiciae009ca399ec36,
  title = {Preliminary geologic map of Rival no.1 quadrangle, North Dakota},
  author = {R. C. Townsend and Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1951},
  doi = {10.3133/ofr51202},
  url = {https://pubs.usgs.gov/publication/ofr51202},
  note = {Source identifier: ofr51202}
}