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2. Adams AB (ed) (1964) Proceedings of the first world conference on national parks. National Park Service, Department of the Interior, Washington, DC, 471 pp
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4. American Association for the Advancement of Science (1925) A resolution bearing on the introduction of non-native plants and animals into the national parks of the United States. In: Grinnell GB, Sheldon C (eds) Hunting and conservation: the book of the Boone and Crockett Club. Yale University Press, New Haven
5. American Planning and Civic Association (circa 1938) Portfolio on the national park and monument system. Part II: conservation of nature. American Civic Association, Washington, DC