Sarah G. Allen, Joe Mortenson & Sophie Webb (2011). "Risso's dolphin, Grampus griseus". Field Guide to Marine Mammals of the Pacific Coast: Baja, California, Oregon, Washington, British Columbia. California Natural History Guides. University of California Press. pp. 301–308. ISBN 978-0-520-26545-5. Alirita la 19an de Novembro 2018.