This article was published about a quarter of a century ago. Now it is available on the Web, on a site of Oberösterreichisches Landesmuseum:
• Josef Reichholf, 1988 – Der Schlangenadler Circaetus gallicus in Bayern: Ein seltener aber regelmäßiger Durchzügler am Alpennordrand [The Short-toed Eagle in Bavaria: A Rare but Regular Migrant Along the Northern Fringe of the Alps] // Anzeiger der Ornithologische Gesellschaft in Bayern, 27 (1): 115-124. – 
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