@Hix: it's easily available online and is the most comprehensive book of zoo reviews ever published. There are rankings of the top 10 zoos in 20 different categories, two separate lists of the top 25 exhibits, and several pages of detailed information on each of the top 60 zoos. There are close to 100 zoos analyzed throughout the book, and the only perceivable flaw is that it is only for U.S. zoos. Since many of the world's great zoos are found in America then perhaps that isn't such a flaw after all...haha.
