@misc{indiciaef87cc6c0382f,
  title = {Geology and ground-water hydrology of the Angostura irrigation project, South Dakota, with a section on the mineral quality of the waters},
  author = {Robert T. Littleton and Herbert A. Swenson},
  year = {1949},
  doi = {10.3133/cir54},
  url = {https://pubs.usgs.gov/publication/cir54},
  note = {Source identifier: cir54}
}