@misc{indiciae5aa1dbbee4f1,
  title = {George Engelmann : botanical notebook 9 : Echinocereus, Cereus, Eulychnia, Pilocereus — Illustration, [No.] 2069 verso},
  url = {https://www.biodiversitylibrary.org/page/56139917},
  note = {Source identifier: page-56139917}
}