The Raven's Gift: A Scientist, a Shaman, and Their Remarkable Journey Through the Siberian Wilderness by Jon Turk (2010, St. Martin's Press).
Jon Turk has a PhD in organic chemistry from the University of Colorado (hence "scientist" in the title) but seems to have worked most of his professional life as a environmental and geoscience textbook author. His great love is adventure travel and he's kayaked the North Pacific, biked through the Gobi, rock climbed on Baffin Island, and, of course, traveled in the Siberian wilderness (Kamchatka Peninsula area) among other things.
I picked up this book for two reasons - first, as I've mentioned in a previous post, I like reading books about travel to exotic locales I'll likely never see. Second, never mentioned before in this blog, is that I have had an interest in shamansim stretching for many years (I think it started many, many years ago when, as a young college student, I took a class called Psychology of Consciousness with Dr. Stephen Larson, author of The Shaman's Doorway: Opening Imagination to Power and Myth).