@misc{indiciaec28dbaaf2f9a,
  title = {George Engelmann : botanical notebook 7 : Echinocactus, Echinopsis, and Cereus — Illustration, [No.] 1703},
  year = {1870},
  url = {https://www.biodiversitylibrary.org/page/56167076},
  note = {Source identifier: page-56167076}
}