Perrin, W.F.; Würsig, B.; Thewissen, J.G.M. (2009). Encyclopedia of marine mammals. Second edition. Academic Press: London. ISBN 978-0-12-373553-9. xxix, 1316 pp. (look up in IMIS) [details]
Bulls' mean standard length is 180 cm (170-200) and mean weight 133 kg (90-197).