Tom Brown, Jr., "The Science and Art of Tracking: Nature's Path to Spiritual Discovery," 1999, about 210 pages. Notable for two things: great detail on learning the theory of pressure releases accompanied by many diagrams and photographs; and a lot of spiritual assertions. I also found a lot of useful general tracking information in this book.

I will do a separate commentary on this book along with three other Tom Brown, Jr. books I read a bit later.