@misc{indiciaed8456956ee0a,
  title = {Behaviour patterns of Mallard Anas Platyrhynchos pairs and broods in Minnesota and North Dakota},
  author = {P.J. Pietz and D. A. Buhl},
  year = {1999},
  url = {https://pubs.usgs.gov/publication/70021601},
  note = {Source identifier: 70021601}
}