Influence

[Danial]

Everyone knows that the makers of this game took their ideas from popular UFO folklore at the time of production, right? Well, I remember back in the early 90's (just before the game was made), flicking through a book that contained a kind of alien encyclopedia, using "witness accounts" to compile a list of all the different kinds of aliens that have visited Earth. I remember there were the usual greys, floating hooded ones, green humanoid ones, and even a half-snake one. Obviously these correspond to the Sectoids, Ethereals, Mutons, and Snakemen respectively. Now, my question is: Does anyone happen to know which book this might have been? There are so many books out there on aliens and UFOs that I have no idea where to start looking.