Read, A.J.; Wiepkema, P.R.; Nachtigall, P.E. (1997). The harbour porpoise (Phocoena phocoena), in: Read, A.J. et al.The biology of the harbour porpoise. pp. 3-6
In: Read, A.J.; Wiepkema, P.R.; Nachtigall, P.E. (1997). The biology of the harbour porpoise. De Spil Publishers: Woerden. ISBN 90-72743-07-5. XV, 410 pp., meer