@misc{indiciae21ef3f323be5,
  title = {Twin embryos in a peregrine falcon egg},
  author = {O. H. Pattee and W.G. Mattox and W.S. Seegar},
  year = {1984},
  doi = {10.2307/1367013},
  url = {https://pubs.usgs.gov/publication/5221918},
  note = {Source identifier: 5221918}
}