@misc{indiciae9425a3020721,
  title = {George Engelmann : botanical notebook 7 : Echinocactus, Echinopsis, and Cereus — Illustration, [No.] 1701},
  year = {1870},
  url = {https://www.biodiversitylibrary.org/page/56167072},
  note = {Source identifier: page-56167072}
}