@misc{indiciae68e8fab77c02,
  title = {3,800-Myr granitic gneiss in south-western Minnesota},
  author = {S. S. Goldich and C. E. Hedge},
  year = {1974},
  doi = {10.1038/252467a0},
  url = {https://pubs.usgs.gov/publication/70001295},
  note = {Source identifier: 70001295}
}