@misc{indiciae0b9b320007bf,
  title = {Ground-water levels and directions of flow in the vicinity of a well field, Elkhart, Indiana, December 1989},
  author = {R.F. Duwelius and Lee R. Watson},
  year = {1992},
  doi = {10.3133/ofr9255},
  url = {https://pubs.usgs.gov/publication/ofr9255},
  note = {Source identifier: ofr9255}
}