@misc{indiciae1a3da85edcc5,
  title = {The distribution of selected elements and minerals in soil of the conterminous United States},
  author = {Laurel G. Woodruff and William F. Cannon and David B. Smith and Federico Solano},
  year = {2015},
  doi = {10.1016/j.gexplo.2015.01.006},
  url = {https://pubs.usgs.gov/publication/70191255},
  note = {Source identifier: 70191255}
}