Reijnders, Peter JH, Sophie MJM Brasseur, Svend Tougaard, Ursula Seibert, Thomas Borchardt, and Michael Stede. “Population development and status of harbour seals (<i>Phoca vitulina</i>) in the Wadden Sea”. NAMMCO Scientific Publications 8 (September 1, 2010): 95–105. Accessed January 8, 2025. https://new.eludamos.org/index.php/NAMMCOSP/article/view/2677.