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↑Mayr, G. 2004. «A partial skeleton of a new fossil loon (Aves, Gaviiformes) from the early Oligocene of Germany with preserved stomach content.» Journal of Ornithology145: 281—286. doi:10.1007/s10336-004-0050-9PDf fulltext [Архівовано 24 вересня 2015 у Wayback Machine.]