@misc{indiciaec21bce968ce0,
  title = {Nonlinear least-squares inversion of bipole-bipole direct-current data (program NLSBPBP)},
  author = {W.L. Anderson},
  year = {1987},
  doi = {10.3133/ofr8795},
  url = {https://pubs.usgs.gov/publication/ofr8795},
  note = {Source identifier: ofr8795}
}