@misc{indiciaee49c92705928,
  title = {The Grand Gulch mining region, Mohave County, Arizona},
  author = {J. M. Hill},
  year = {1915},
  doi = {10.3133/b580d},
  url = {https://pubs.usgs.gov/publication/b580D},
  note = {Source identifier: b580D}
}