@misc{indiciaed90729cf2724,
  title = {Map showing chromium, molybdenum, tin, tungsten, and vanadium deposits of South America},
  author = {G. H. Goudarzi},
  year = {1977},
  doi = {10.3133/mf868b},
  url = {https://pubs.usgs.gov/publication/mf868B},
  note = {Source identifier: mf868B}
}