@misc{indiciae8ea93a76a435,
  title = {George Engelmann : botanical notebook 9 : Echinocereus, Cereus, Eulychnia, Pilocereus — Illustration, [No.] 2106},
  year = {1869},
  url = {https://www.biodiversitylibrary.org/page/56134345},
  note = {Source identifier: page-56134345}
}