@misc{indiciae5a13141bee41,
  title = {Correspondence : Gray (Asa) and Engelmann (George), 1841-1883 — Illustration, Jun 22 / 1843 1},
  year = {1843},
  url = {https://www.biodiversitylibrary.org/page/42009926},
  note = {Source identifier: page-42009926}
}