United States. Department of the Interior & United States. Servicio de Parques Nacionales. (1993). Guiding principles of sustainable design. National Park Service.
Cita Chicago Style (17a ed.)United States. Department of the Interior e United States. Servicio de Parques Nacionales. Guiding Principles of Sustainable Design. Denver, United States: National Park Service, 1993.
Cita MLA (8a ed.)United States. Department of the Interior e United States. Servicio de Parques Nacionales. Guiding Principles of Sustainable Design. National Park Service, 1993.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.