George Engelmann : botanical notebook 13 : Opuntia - Engelmann, George, (1868)
https://www.biodiversitylibrary.org/bibliography/127603
Keywords: 1809-1884|1814-1875|Botanical illustration|Cactaceae|Cactus|Engelmann; George; |North America|Opuntia|Plant collecting|Plants|Schott; Arthur; |