@misc{indiciaee4ce92af0ca2,
  title = {Generalized slope map of the Henrys Lake Quadrangle, Idaho and Montana},
  author = {I. J. Witkind},
  year = {1972},
  doi = {10.3133/i781b},
  url = {https://pubs.usgs.gov/publication/i781B},
  note = {Source identifier: i781B}
}