@misc{indiciaeb204bc138731,
  title = {George Engelmann : botanical notebook 9 : Echinocereus, Cereus, Eulychnia, Pilocereus — Illustration, [No.] 2036},
  url = {https://www.biodiversitylibrary.org/page/56141872},
  note = {Source identifier: page-56141872}
}