48 insufficient knowledge and experience. There is even the high risk that erroneous conclusions are drawn. REFERENCES: Dahlmann, G.: Eine neue sichere Methode zur Identifizierung der Verursacher von Ölverschmutzungen (Dt. hydrogr. Z. 37(5), 1984, 217-220) Dahlmann, G: Identification of oil pollution. In: Seminar on Oil Pollution Questions, Norrköping, (Baltic Sea Environment Proceedings No. 22, Baltic Marine Environment Protection Commission - Helsinki Commission, 1987, 149-160) Dahlmann G., Timm D., Averbeck Chr., Camphuysen C., Skov H., Durinck J.: Oiled Seabirds- Comparative Investigations on Oiled Seabirds and Oiled Beaches in the Netherlands, Denmark and Germany (1990-93)(Mar. Poll. Bull., Vol. 28, No. 5, 305- 310, 1994) Dahlmann, G. Müller-Navarra, S.: The Source of Oil Pollution on the East Frisian islands in October 1989 - an Exemplary case (Dt. Hydrogr. Z. 49, 35-43, 1997 Author: Dr. Gerhard Dahlmann Bundesamt für Seeschifffahrt und Hydrographie, Hamburg and Rostock Tel: +49/40/3190-3352 e-mail: gerhard.dahlmann@bsh.de