The book I’m after was a spooky children’s book picked up at a R.I.F. book fair in the early 80s. It was from a UK line of books and I believe was titled, simply, “UFOs.” It was perfectly square, tiny (a bit larger than a piece of toast), softcover, short (maybe 24 pages or less), and had realistic and creepy paintings of supposedly true UFO case files. Lots of art, light text. The cover was entirely midnight blue, and either had no art at all, or perhaps just a small clip of art from within, probably a “grey” alien face if anything. I had another book from the line that I believe was called “Dinosaurs,” and followed the same format, but had a vivid green cover. It was definitely an entire line of small books. Oh, and I remember the UFO book was the first place I ever heard of the Men in Black, though they seemed a lot creepier in the book than in the movie. I think the entry on their mysterious origins (it was acknowledged no one knew if they were extraterrestrial or government agents) mentioned one of them putting his fingers in a cup of coffee as if he didn’t understand it. Or something like that!