The editor (National Institute for Discovery Science) is the institute founded by the famous Jacques Vallée (but is not obliged to believe his theories sometimes whimsical). That said, this book has nothing to do with J.Vallée. The author describes the main UFO notifications occurred in Europe since the sixteenth century. Among the strangest and supported by hard evidence or records cases it describes in particular the triangles of the Belgian wave, the English notifications, statements radar, electromagnetic interference or debris collected in Denmark.