@misc{indiciae7dafcba0b84a,
  title = {Population ecology of the mallard: I. A review of previous studies and the distribution and migration from breeding areas},
  author = {David R. Anderson and Charles J. Henny},
  year = {1972},
  url = {https://pubs.usgs.gov/publication/rp105},
  note = {Source identifier: rp105}
}