George Engelmann : botanical notebook 14 : Pereskia, Mammillaria, Cereus, Echinocactus, Pilocereus, Opuntia and cactus - Engelmann, George, (1873)
https://www.biodiversitylibrary.org/bibliography/128312
Keywords: 1805-1877|1809-1884|Botanical illustration|Braun; Alexander; |Cactaceae|Cactus|Cereus|Correspondence|Echinocactus|Engelmann; George; |Mammillaria (Cactus)|North America|Opuntia|Pereskia|Pilocereus|Plant collecting|Plants|