Leuenberger B. E., Pereskia, Maihuenia, and Blossfeldia—Taxonomic History, Updates, and Notes, Haseltonia, 2008, 14:54-93, doi: 10.2985/1070-0048-14.1.54
The account documents name history and observations of living leafy cacti, Maihuenia and Blossfeldia. It also contains greenhouse accounts of unusual roots and germination within fruits.