View all references for Sea squirts, fish, reptiles, birds and mammals (phylum Chordata)
(1971). Field guide of whales and dolphins. Amsterdam: Publishing Company Tors.
(1997). The species directory of the marine fauna and flora of the British Isles and surrounding seas. Belfast: Ulster Museum. [Ulster Museum publication, no. 276.]
(1994). FAO species identification guide. Marine mammals of the world. Rome: United Nations Environment Programme, Food and Agriculture Organization of the United Nations.
(2002). Photographic Guide to the Marine Mammals of the North Atlantic. Oxford: Oxford University Press.
(2003). Atlas of Cetacean Distribution in North-west European Waters. Peterborough: Joint Nature Conservation Committee.