Threats to the harbour seal population in the Wadden Sea
Reijnders, P.J.H. (1981). Threats to the harbour seal population in the Wadden Sea, in: Reijnders, P. et al. (Ed.) Marine mammals of the Wadden Sea: final report of the section 'Marine Mammals' of the Wadden Sea Working Group. Reports of the Wadden Sea Working Group, 7: pp. 38-47
In: Reijnders, P.; Wolff, W.J. (Ed.) (1981). Marine mammals of the Wadden Sea: Final report of the section 'Marine Mammals' of the Wadden Sea Working Group. Reports of the Wadden Sea Working Group, 7. Stichting Veth tot Steun aan Waddenonderzoek: Leiden. ISBN 90-6191-057-9. 64 pp., meer
