@misc{indiciae8559ebc08a6c,
  title = {Bird populations in east central Illinois : fluctuations, variations, and development over a half-century / Illinois biological monographs — Illustration, BHL page 33736630},
  year = {1982},
  url = {https://www.biodiversitylibrary.org/page/33736630},
  note = {Source identifier: page-33736630}
}