@misc{indiciae7215221e11c3,
  title = {A semiquantitative spectrographic method for the analysis of minerals, rocks, and ores (II)},
  author = {C. L. Waring and C.A. Annell},
  year = {1952},
  doi = {10.3133/tei215},
  url = {https://pubs.usgs.gov/publication/tei215},
  note = {Source identifier: tei215}
}