@misc{indiciae72142dc85a00,
  title = {Nationwide organochlorine and mercury residues in wings of adult mallard and black ducks during the 1969-70 hunting season},
  author = {R.G. Heath and S.A. Hill},
  year = {1974},
  url = {https://pubs.usgs.gov/publication/5221212},
  note = {Source identifier: 5221212}
}