Washington State Planning Council & United States. National Park Service. (1941). A study of parks, parkways, and recreational areas.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रWashington State Planning Council और United States. National Park Service. A Study of Parks, Parkways, and Recreational Areas. [Olympia, 1941.
एमएलए (8वां संस्करण) प्रशस्ति पत्रWashington State Planning Council और United States. National Park Service. A Study of Parks, Parkways, and Recreational Areas. 1941.
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