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Covers 10,721 species accounts from every bird species in the world. This source combines content, data, multimedia, figures, and illustrations from four different ornithological volumes: Birds of North America (BNA), Neotropical Birds, Handbook of Birds of the World (HBW Alive), and Bird Families of the World.
Published for the American Physiological Society by Wiley Blackwell, "Comprehensive Physiology is the most authoritative and comprehensive collection of physiology information ever assembled, and uses the most powerful features of review journals and electronic reference works."