@misc{indiciaed100bef39161,
  title = {Mineral resource potential of the NB-20-4 Quadrangle, eastern Guayana Shield, Bolivar State, Venezuela},
  author = {Jeffrey C. Wynn and Gary B. Sidder},
  year = {1991},
  doi = {10.3133/b1960},
  url = {https://pubs.usgs.gov/publication/b1960},
  note = {Source identifier: b1960}
}