@misc{indiciae5e4632500b62,
  title = {Spectrochemical computer analysis - argon-oxygen d-c arc method for silicate rocks},
  author = {A. F. Dorrzapf},
  year = {1973},
  url = {https://pubs.usgs.gov/publication/70161894},
  note = {Source identifier: 70161894}
}