@misc{indiciaeed0117a39b7a,
  title = {Minor and trace element contents of kimberlites of the Front Range, Colorado and Wyoming},
  author = {M. E. McCallum and C.B. Smith},
  year = {1978},
  doi = {10.3133/ofr781011},
  url = {https://pubs.usgs.gov/publication/ofr781011},
  note = {Source identifier: ofr781011}
}