I find books, generally speaking, more authoritative than most documentaries. The added advantage is one can contrast and compare the works of different authors, they each bring their own version of reality to it. For example, one can read Liddell Hart's History of the Second World War and get some misapprehensions, in my view, not really born out in other studies, but parallel to what Guderian claimed in his autobiography, and curiously the two collaborated to a degree.
But that's just me of course, I'd rather read than watch TV.
