Scheffer, V.B. (1958). Systematic account, in: Scheffer, V.B. Seals, sea lions and walruses. A review of the Pinnipedia. pp. 52-134
In: Scheffer, V.B. (1958). Seals, sea lions and walruses: A review of the Pinnipedia. Stanford University Press: Stanford, California. ISBN 0-8047-0544-5. 179 pp., more
