-. (1989). Nature's wonderlands: National park of the world. National geography society.
芝加哥风格引文-. Nature's Wonderlands: National Park of the World. Washington: National geography society, 1989.
MLA引文-. Nature's Wonderlands: National Park of the World. National geography society, 1989.
警告:这些引文格式不一定是100%准确.