@misc{indiciae1a2a09eca910,
  title = {George Engelmann : botanical notebook 9 : Echinocereus, Cereus, Eulychnia, Pilocereus — Illustration, [No.] 2091},
  url = {https://www.biodiversitylibrary.org/page/56139946},
  note = {Source identifier: page-56139946}
}