@misc{indiciaeca222da2f93c,
  title = {George Engelmann : botanical notebook 9 : Echinocereus, Cereus, Eulychnia, Pilocereus — Illustration, [No.] 2064},
  url = {https://www.biodiversitylibrary.org/page/56139906},
  note = {Source identifier: page-56139906}
}