basis of recordShirihai, H. (2002). A complete guide to Antarctic Wildlife: the Birds and Marine Mammals of the Antarctic Continent and the Southern Ocean. Alula Press FI 510 pp.[details]
additional sourceBerta, A.; Churchill, M. (2012). Pinniped taxonomy: review of currently recognized species and subspecies, and evidence used for their description. <em>Mammal Review.</em> 42(3), 207-234.[details]