European Union action plans for eight priority bird species : bittern (Botaurus stellaris), ferruginous duck (Aythya nyroca), Steller's eider (Polysticta stelleri), lammergeier (Gypaetus barbatus), greater spotted eagle (Aquila clanga), lesser spotted eagle (Aquila pomarina), Bonelli's eagle (Hieraaetus fasciatus), little bustard (Tetrax tetrax) / edited by Norbert Schäffer and Umberto Gallo-Orsi. - Schäffer, Norbert; Gallo-Orsi, Umberto (Office for Official Publications of the European Communities, 2001)