@misc{indiciae2c721d8f88ab,
  title = {Mineralogy and stratigraphy of the lower part of the Pierre Shale, South Dakota and Nebraska},
  author = {L.G. Schultz},
  year = {1965},
  doi = {10.3133/pp392b},
  url = {https://pubs.usgs.gov/publication/pp392B},
  note = {Source identifier: pp392B}
}