@misc{indiciaeb55a95e7059d,
  title = {The occurrence of extractable elements in soils from the northern Great Plains},
  author = {J.M. McNeal and R. C. Severson and Larry P. Gough},
  year = {1985},
  doi = {10.2136/sssaj1985.03615995004900040017x},
  url = {https://pubs.usgs.gov/publication/70012191},
  note = {Source identifier: 70012191}
}