@misc{indiciae2ab8a9bb037a,
  title = {Basic concepts in three-part quantitative assessments of undiscovered mineral resources},
  author = {D.A. Singer},
  year = {1993},
  doi = {10.1007/bf02272804},
  url = {https://pubs.usgs.gov/publication/70018261},
  note = {Source identifier: 70018261}
}