@misc{indiciae4b1d9ed4dff0,
  title = {Metallic mineral resources map of the Petersburg Quadrangle, Alaska},
  author = {E. H. Cobb},
  year = {1972},
  doi = {10.3133/mf415},
  url = {https://pubs.usgs.gov/publication/mf415},
  note = {Source identifier: mf415}
}