@misc{indiciae959b36491c6f,
  title = {Map showing distribution pattern of strontium from samples of the nonmagnetic fraction of heavy-mineral concentrates, northern Sonora, Mexico},
  author = {Margaret Hinkle and S.K. McDanal and George Benitez and Luis Chavez},
  year = {1977},
  doi = {10.3133/ofr77339},
  url = {https://pubs.usgs.gov/publication/ofr77339},
  note = {Source identifier: ofr77339}
}