Παραπομπή APA
National Geographic Society (U.S.). (1998). The National Geographic maps: Every foldout map from National Geographic magazine on CD-ROM. Washington, D.C.: National Geographic Society.
Παραπομπή Chicago StyleNational Geographic Society (U.S.). The National Geographic Maps: Every Foldout Map From National Geographic Magazine On CD-ROM. Washington, D.C.: National Geographic Society, 1998.
Παραπομπή MLANational Geographic Society (U.S.). The National Geographic Maps: Every Foldout Map From National Geographic Magazine On CD-ROM. Washington, D.C.: National Geographic Society, 1998.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.