Sangster, George; Knox, Alan G.; Helbig, Andreas J. & Parkin, David T. (2002): Taxonomic recommendations for European birds. Ibis144(1): 153–159. doi:10.1046/j.0019-1019.2001.00026.xabstrakt
Padilla, J. A.; Martinez-Trancón, M.; Rabasco, A. & Fernández-García, J. L. (1999): The karyotype of the Iberian imperial eagle (Aquila adalberti) analyzed by classical and DNA replication banding. Cytogenetics and Cell Genetics84: 61–66. doi:10.1159/000015216 (HTML abstract)
iucnredlist.org
oldredlist.iucnredlist.org
BirdLife International 2012 Aquila heliaca. Från: IUCN 2015. IUCN Red List of Threatened Species. Version 2015.4 www.iucnredlist.org. Läst 24 juni 2016.
iucnredlist.org
BirdLife International 2012 Aquila heliaca. Från: IUCN 2015. IUCN Red List of Threatened Species. Version 2015.4 www.iucnredlist.org. Läst 24 juni 2016.
wiley.com
onlinelibrary.wiley.com
Sangster, George; Knox, Alan G.; Helbig, Andreas J. & Parkin, David T. (2002): Taxonomic recommendations for European birds. Ibis144(1): 153–159. doi:10.1046/j.0019-1019.2001.00026.xabstrakt