@misc{indiciae1ad860f75bec,
  title = {Extraction spectrophotometric determination of niobium in rocks with sulfochlorophenol S},
  author = {A. E. Childress and L. P. Greenland},
  year = {1980},
  doi = {10.1016/s0003-2670(01)84330-0},
  url = {https://pubs.usgs.gov/publication/70010395},
  note = {Source identifier: 70010395}
}