↑U. S. Fish and Wildlife Service, 1990Endangered and Threatened Wildlife and Plants; Determination of Threatened Status for the Plant Harrisia portoricensis (higo chumbo) Federal Register, vol. 55, no. 153
↑ 7.07.1Roskov Y., Kunze T., Orrell T., Abucay L., Paglinawan L., Culham A., Bailly N., Kirk P., Bourgoin T., Baillargeon G., Decock W., De Wever A., Didžiulis V. (ed) (2014). "Species 2000 & ITIS Catalogue of Life: 2014 Annual Checklist". Catalogue of Life. Species 2000: Reading, UK. Ginkuhà 26 Mayo 2014.CS1 maint: multiple names: authors list (link) CS1 maint: extra text: authors list (link)