@misc{indiciaefab6aa0d0e20,
  title = {Copper},
  author = {Waldemar Lindgren and F.B. Weeks and V. C. Heikes},
  year = {1908},
  doi = {10.3133/b340b},
  url = {https://pubs.usgs.gov/publication/b340B},
  note = {Source identifier: b340B}
}