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Blue links lead to the completely translated html versions of the respective page or the respective point on this page, purple to pages whose start pages (as well as introductions and tables of contents at least) are already set up, grey means that no file or translation is available yet.)
Comments in this colour and between two / are from the operator of the German mirror site and translator.Copyright Dr. Eng. Jan Pająk
Img.112 (#D3ab): Two photographs of a cloud shaped like a ring taken by JG. My own sighting of almost identical ring-shaped "cloud-UFO" like that above is described in item #C2. of the web page "UFOs behind clouds".
Visitors since 23.08.2025: (english sites)
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