WIGMAN AB & VRIES TG DE (1941) New cases of the tufted duck Aythya breeding fuligula (L.). LIMOSA 14 (1): 53-59.

Tufted Duck Aythya fuligula My already at the spring meeting of the Club-1941, held in Wolfheze, strong suspicion that the tufted duck breeding could be expected in the floodplains of the Rhine near Wageningen accounts The Grebbe (prov. Utrecht), has since come true, to my satisfaction

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