I cannot trust this source. I wish all descriptions were marked geographically. There is little precise knowledge you can gain while reading the book, as you do not know which culture is referred to. Too pop sciency with too many repetitions of the obvious.
I wish the author told me why in his opinion there is no shamanism in Africa and why he put "sic" in a quote that described shamanism as a religion.
Also I wish the book described to a greater extent other people involved in shamanism besides the shaman.