Invertebrates of the Wadden Sea: final report of the section 'Marine Zoology' of the Wadden Sea Working Group
Dankers, N.M.J.A.; Kühl, H.; Wolff, W.J. (1981). Invertebrates of the Wadden Sea: final report of the section 'Marine Zoology' of the Wadden Sea Working Group. Wadden Sea Working Group Report, 4. A.A. Balkema: Rotterdam. ISBN 90-6191-054-4. 221 pp.