@misc{indiciaea278ba441153,
  title = {Preliminary map showing sand and gravel deposits of North Dakota},
  author = {D. M. Larrabee and L.C. Huff and C. Ahlman},
  year = {1946},
  doi = {10.3133/mb3},
  url = {https://pubs.usgs.gov/publication/mb3},
  note = {Source identifier: mb3}
}