@misc{indiciae77866f07a17f,
  title = {Rare earths in phosphorites: Geochemistry and potential recovery},
  author = {Z. S. Altschuler and Sol Berman and Frank Cuttitta},
  year = {1966},
  doi = {10.3133/ofr663},
  url = {https://pubs.usgs.gov/publication/ofr663},
  note = {Source identifier: ofr663}
}