KATE CGB TEN (1934) Short announcements: Black-headed Gull Larus ridibundus with German ring, found near Kampen. LIMOSA 7 (2): 85-85.

Black-headed Gull Chroicocephalus ridibundus = Larus ridibundus Black-headed Gull Larus ridibundus with German ring, found near Kampen

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