Larridon I., Veltjen E., Semmouri I., Asselman P., Guerrero P. C., Duarte M., Walter H. E., Cisternas M. A., Samain M. S., Investigating taxon boundaries and extinction risk in endemic Chilean cacti (Copiapoa subsection Cinerei, Cactaceae) using chloroplast DNA sequences, microsatellite data and 3D mapping, Kew Bulletin, 2018, 73(4):55, doi: 10.1007/s12225-018-9780-3
The paper compares chloroplast sequences, microsatellite markers and population mapping in the Copiapoa cinerea group. It includes detailed descriptions of C. cinerea and its subspecies and C. gigantea, with an analysis of their separation and ranges.