@misc{indiciaedf90f5a8e805,
  title = {A spectrographic method for determining the hafnium-zirconium ratio in zircon},
  author = {C. L. Waring and H.W. Worthing},
  year = {1956},
  doi = {10.3133/b1036f},
  url = {https://pubs.usgs.gov/publication/b1036F},
  note = {Source identifier: b1036F}
}