(2011). National geographic. Washington, DC: National Geographic Society.
Trích dẫn kiểu ChicagoNational Geographic. Washington, DC: National Geographic Society, 2011.
Deismireacht MLANational Geographic. Washington, DC: National Geographic Society, 2011.
Rabhadh: D'fhéadfadh nach mbeadh na deismireachtaí seo 100% cruinn i gcónaí.