A 1950s study of the UFO phenomenon and an analysis on whether or not the pilots come in peace or something more sinister. Reprinted with additional material here in 1967.
1967 ACE Books paperback, with a striking cover design.
Some marks to the covers as well as rubbing, creasing and bumping, most notably at the bottom of the spine. Sound in the binding and clean, though somewhat faded as is usual in 1960s mass market paperbacks.
