United States. National Capital Park and Planning Commission. (1950). Open spaces and community services: A portion of the comprehensive plan for the national capital and its environs. The Commission.
Παραπομπή σε μορφή Chicago (17η εκδ.)United States. National Capital Park and Planning Commission. Open Spaces and Community Services: A Portion of the Comprehensive Plan for the National Capital and Its Environs. Washington: The Commission, 1950.
Παραπομπή σε μορφή MLA (8th εκδ.)United States. National Capital Park and Planning Commission. Open Spaces and Community Services: A Portion of the Comprehensive Plan for the National Capital and Its Environs. The Commission, 1950.
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