I have been reading Richard Dolan's "The Coverup Exposed" on my lunch hour (on those occasions when I get a lunch break), and I've been able to enjoy it by keeping a couple of thoughts in mind... First, Dolan seems to lean toward the extra-terrestrial hypothesis. I'm not sure that I do, but that's okay. Neither one of us knows for sure. Still, I have to filter his analysis through a different lens. Whereas Dolan sees physical-seeming craft engaging in all sorts of tricksterish behavior with an implicit goal of monitoring or engaging our technological state, visible to anyone who stumbles upon them, I see apparitions of craft appearing to specific individuals; or, more possibly, specific (select) people who are somehow able to peek behind our physical curtain, and see things outside our consensus physical reality that most usually can't. Second, some of the cases that are cited as authoritative have problems, and I've gotten into the habit of checking them out to see if they have been "debunked." (A handful apparently have been.) But I don't fault Dolan. He has created a monumental study of hundreds of cases, but they were compiled BG (before Google). Since I haven't done the research myself or written my own UFO book, I can't gainsay anything of Dolan's.
So I'm now on to Timothy Green Beckley's "Mystery Of The Men In Black" and "Humanoid Encounters" by Albert Rosales. I actually think that the MIB phenomenon is more interesting than the UFOs it purports to represent, but I haven't found many serious studies on it. Cross-discipline paranormalists spend much energy wondering if MIB and various humanoid sightings are "connected" somehow to UFOs, and what it all might "mean"--but I wonder why, if it's a physical phenomenon, it's not more universally observable. It seems like it should be, if, in fact, it is physical.