@misc{indiciaeb933a7c0d3e7,
  title = {George Engelmann : botanical notebook 9 : Echinocereus, Cereus, Eulychnia, Pilocereus — Illustration, [No.] 2069},
  url = {https://www.biodiversitylibrary.org/page/56139916},
  note = {Source identifier: page-56139916}
}