@misc{indiciae3d28b32d7bb8,
  title = {Economic heavy minerals in glaciofluvial sediments of Minnesota},
  author = {Gretchen Luepke},
  year = {1993},
  doi = {10.3133/ofr93345},
  url = {https://pubs.usgs.gov/publication/ofr93345},
  note = {Source identifier: ofr93345}
}