@misc{indiciaede98c8a56663,
  title = {The flame photometric determination of calcium in phosphate, carbonate, and silicate rocks},
  author = {Henry Kramer},
  year = {1957},
  doi = {10.1016/s0003-2670(00)87078-6},
  url = {https://pubs.usgs.gov/publication/70009850},
  note = {Source identifier: 70009850}
}