CAMPHUYSEN CJ (1996) Dutch Ornithological Union: National day 1994: Gulls and the sea: the significance of fish waste for Herring Gulls and Lesser Gull on the islands. LIMOSA 69 (1): 29-29.

Gulls and the sea: the significance of fish waste for Herring Gulls and Lesser Gull on the islands Dutch Ornithological Union: National day 1994: SOVON VBN

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