Visit please Javier Blasco-Zumeta’s site to find some information on identification of birds in nature. This information sheet – 
(En) on two pages with demonstrative photos (moult and age-specific changes) – could be helpful in the field together with article of Guido Premuda and Andrea Corso about the plumage characters. Also we have the fullsized illustrations to view the plumage more particularly.
Here we present three different authors’ texts dedicated to Short-toed Eagles of three different regions: Crimea, Belarus and Turkmenistan. They are extracts…
…from S.A. Bukreev’s book (Ru):
• Букреев С.А., 1997 – Орнитогеография и заповедное дело Туркменистана [Ornithogeography and reserve management of Turkmenistan] – М.: Центр охраны дикой природы (Biodiversity Conservation Center), 159 с.
…from Y.V. Kostin’s book (Ru):
• Костин Ю.В., 1983 – Птицы Крыма [Birds of Crimea] – М.: Наука, 240 с. /map/.
…and from V.V. Ivanovski’s work (Ru):
• Ивановский В.В., 1992 – Трофические связи редких хищных птиц Белорусского Поозерья [Food chains of rare birds of prey of Belarussian Poozer’e] // Оттиск, №173, 66 с. /map/.
New personal site of famous French researcher, Yves Boudoint /map/, has been created. Among the sections there are many different photos of Short-toed Eagles, old and relatively new texts (Fr) and presentations of materials on CD and DVD dedicated to the birds. The site’s content tells its own story.
Three texts dedicated to Short-toed Eagle are presented here. They all are in different formats and knit together by the authors (Guido Premuda, Luca Baghino & Marco Gustin), by a territory of the researches (Italy) /map/ and by year of issue (2006):
• Luciano RUGGIERI, Guido PREMUDA, Luca BAGHINO, Luca GIRAUDO, 2006 – Esperienza di monitoraggio su vasta scala della migrazione autunnale del Biancone Circaetus gallicus in Italia e nel Mediterraneo centrale [A large-scale survey of the autumn migration of Short-toed Eagles across Italy and the Central Mediterranean] // Avocetta, 30: 76-80. – (It) (source – EBN Italia website).
• Luca BAGHINO, Guido PREMUDA, 2006 – Consistente migrazione pre-riproduttiva del Biancone Circaetus gallicus lungo il versante tirrenico ligure-toscano [Substantial pre-reproductive migration of the Short-toed Eagle along the Tyrrhenian coast of Liguria and Tuscany] // Rete Natura 2000 in Liguria: Pubblicazioni – 
(It) (source – Parco del Beigua website).
• Luca BAGHINO, Marco GUSTIN, 2006 – Censimenti dei flussi migratori dei rapaci diurni e altri grandi veleggiatori in transito nella ZPS “Beigua-Turchino” // Rete Natura 2000, Parco del Beigua – (It) (source – Parco del Beigua website).
The last work concerns Short-toed Eagle among other Raptors.
Let us draw your attention to a work of Dimitris E. Bakaloudis, Christos G. Vlachos and Graham J. Holloway on Short-toed Eagle in northeast Greece /map/:
• D.E. Bakaloudis, C.G. Vlachos, G.J. Holloway, 2005 – Nest spacing and breeding performance in Short-toed Eagle Circaetus gallicus in northeast Greece // British Trust for Ornithology, Bird Study, 52: 330–338. – (En).
This text can be found on the Taylor & Francis Online website.
One of works of the oldest Short-toed Eagles researcher in France – Yves Boudoint /map/ – is represented below. This text describes some interesting details of biology of the species and includes notes on some traditional and untraditional methods of study:
• Yves Boudoint, 1953 – Etude de la biologie du Circaète Jean-le-Blanc [Study of the Short-toed Eagle biology] // Alauda, 21 : 86-112. (Fr).
This is the presentation of two old texts of the first part of the XX century. One of them was written by Viktor Zebe:
• Viktor Zebe, Oktober 1936 – Zur biologie des Schlangenadlers [Biology of the Short-toed Eagle] – Berichte des Vereins Schlesicher Ornithologen /map/. Just read the translation of it (Fr) from German made by one of the greatest adepts in Short-toed Eagles in France – Yves Boudoint.
The second is Nikolay Gavrilenko‘s work, that is mentioned in the first one:
• Гавриленко Н.И., 1929 – Птицы Полтавщины. Змееяд [The birds of the Government of Poltava. Short-toed Eagle] // Полтава: Издание Полтавского союза охотников: 28-30 (Ru) /map/.
Just download a scan of the part dedicated to all birds of prey on the Ukrainian Birds of Prey Research Centre website.