@misc{indiciaeb9fd76b942ee,
  title = {Gravity and magnetic features as related to geology in the Leadville 30-minute quadrangle, Colorado},
  author = {Ogden Tweto and James E. Case},
  year = {1972},
  doi = {10.3133/pp726c},
  url = {https://pubs.usgs.gov/publication/pp726C},
  note = {Source identifier: pp726C}
}