@misc{indiciaea2e90c580c3a,
  title = {Analysis of soil reference materials PL-1 and BPGM-1 for the Polish Committee on Standardization Measures and Quality Control},
  author = {S. A. Wilson and Paul H. Briggs and J. S. Mee and D. F. Siems},
  year = {1993},
  doi = {10.3133/ofr93281},
  url = {https://pubs.usgs.gov/publication/ofr93281},
  note = {Source identifier: ofr93281}
}