LEOPOLD M, SKOV H & DURINCK J (1995) Dutch Ornithological Union Themeday Seabirds at sea in the North Sea: The distribution and numbers of Red throated divers Gavia stellata and Black throated divers Gavia arctica in the North Sea. LIMOSA 68 (3): 125-125.

Dutch Ornithological Union Themeday Seabirds at sea in the North Sea: The distribution and numbers of Red throated divers Gavia stellata and Black throated divers Gavia arctica in the North Sea

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