@misc{indiciae4af98c160b7c,
  title = {Uranium and other trace elements in petroleums and rock asphalts},
  author = {K.G. Bell},
  year = {1960},
  doi = {10.3133/pp356b},
  url = {https://pubs.usgs.gov/publication/pp356B},
  note = {Source identifier: pp356B}
}