The proceedings on the 6th International Conference for Conservation of the Eastern Imperial Eagle are available for download:
For the download to work you have to register. It might happen that you will see a Bulgarian website when you click “Download the publication”. Just click on the English icon in the top right corner and the website will change back to English.
This is a must read for anyone interested in the Eastern Imperial Eagle. I don’t know of any publication with more up to date details on the species.
Also see this interview:
Interview with Dimitar Demerdjiev about the Eastern Imperial Eagle in Bulgaria