@misc{indiciaece2803c72281,
  title = {Element associations in soils of the San Joaquin Valley, California},
  author = {R.R. Tidball and R. C. Severson and C. A. Gent and G. O. Riddle},
  year = {1986},
  doi = {10.3133/ofr86583},
  url = {https://pubs.usgs.gov/publication/ofr86583},
  note = {Source identifier: ofr86583}
}