Edwin Elias
Hauke Bietz
Henk Schoorl
Sabine Dittmann
Sabine Dittmann
Henning von Nordheim
International Scientific Wadden Sea Symposium (8th 1993 Esbjerg Denmark)
International Wadden Sea Symposium (7th 1990 Ameland Netherlands)
International Wadden Sea Symposium (7th 1990 Ameland Island Netherlands)
Trilateral Working Conference on Saltmarsh Management in the Wadden Sea Region (2nd 1989 Rømø Denmark)
Jan Veen
J. Ehlers
Jan Veen
International Wadden Sea Symposium (5th 1986 Esbjerg Denmark)
F. Drost
International Wadden Sea Symposium (4th 1983 Texel Netherlands)
W. J. Wolff
W.J. Wolff
J. A. W. de Wit
P. J. H. Reijnders
Wadden Sea Symposium (1981 Norderney Germany)
J. Abrahamse
Wadden Sea Working Group. Terrestrial Fauna.
Berndt Heydemann
W.J. Wolff
Wadden Sea Working Group. Birds.
Sietse van der Hoek
Wadden Sea Working Group. Fishes and Fisheries Section.
Wadden Sea Working Group. Marine Botany Section.
Jan Heuff
Landelijke Vereniging tot Behoud van de Waddenzee. Werkgroep Rekreatie.
Netherlands. Geologische Dienst.
Studiedag Rekreatie Leeuwarden 1977.
Eisma D. Dr.
Netherlands.
Netherlands. Ministerie van Volkshuisvesting en Ruimtelijke Ordening.
Conference of Wadden Sea Experts (1975 Schiermonnikoog Netherlands)
Pieter Terpstra
Pieter Terpstra
P. J. G. Polderman
G. Groustra
Netherlands (Kingdom 1815- ). Waddenzeecommissie.