@misc{indiciae9ed8cfc07ebc,
  title = {Bathymetric contour maps of lakes surveyed in Iowa in 2004},
  author = {S. Mike Linhart and Kris D. Lund},
  year = {2006},
  doi = {10.3133/sim2949},
  url = {https://pubs.usgs.gov/publication/sim2949},
  note = {Source identifier: sim2949}
}