@misc{indiciaeba13113ecd2d,
  title = {Bedrock geologic map showing configuration of the bedrock surface in the Nebraska part of the Sioux City 1 degree by 2 degrees Quadrangle},
  author = {R.R. Burchett and V. H. Dreeszen and V. L. Souders and G.E. Prichard},
  year = {1988},
  doi = {10.3133/i1879},
  url = {https://pubs.usgs.gov/publication/i1879},
  note = {Source identifier: i1879}
}