LUTEYN, J. L. and PEDRAZA-PEÑALOSA, P. (2013) “Nomenclature, taxonomy, and conservation of the neotropical genus Sphyrospermum (Ericaceae: Vaccinieae), including five new species for Colombia, Ecuador, and Peru”, Phytotaxa, 79(1), pp. 1–29. doi: 10.11646/phytotaxa.79.1.1.