Yeah, EVERYBODY was at least quoted in the book. There's plenty of quotes that are seemingly MJ directly talking to Sam Smith. There's a dfference between simple journalism and sources.
And the thing is, people who act like that book was some major MJ smear campaign haven't actually read the damn thing. It's pretty fair...but as we know, MJ's a psychopath, so the truth is pretty damning if you give it enough material to begin with. He covers the bad AND the good. Even showing his sympathetic side talking about how depressed he was after Magic's HIV announcement and Sam Smith seemingly takes his side for refusing to go to the White House in '92.