United States. Department of the Interior & United States. Servicio de Parques Nacionales. (1993). Guiding principles of sustainable design. National Park Service.
Chicago-Zitierstil (17. Ausg.)United States. Department of the Interior und United States. Servicio de Parques Nacionales. Guiding Principles of Sustainable Design. Denver, United States: National Park Service, 1993.
MLA-Zitierstil (8. Ausg.)United States. Department of the Interior und United States. Servicio de Parques Nacionales. Guiding Principles of Sustainable Design. National Park Service, 1993.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.