@misc{indiciaecc4a8fff19f2,
  title = {Chemical variation of soils in Missouri associated with selected levels of the soil classification system},
  author = {R.R. Tidball},
  year = {1976},
  doi = {10.3133/pp954b},
  url = {https://pubs.usgs.gov/publication/pp954B},
  note = {Source identifier: pp954B}
}