@misc{indiciae9a0097530091,
  title = {George Engelmann : botanical notebook 9 : Echinocereus, Cereus, Eulychnia, Pilocereus — Illustration, [No.] 2142 2},
  url = {https://www.biodiversitylibrary.org/page/56150091},
  note = {Source identifier: page-56150091}
}