APA (7th ed.) Citation

National Geographic Society (U.S.). Geographic school bulletins. National Geographic Society.

Chicago Style (17th ed.) Citation

National Geographic Society (U.S.). Geographic School Bulletins. [Washington]: National Geographic Society.

MLA (8th ed.) Citation

National Geographic Society (U.S.). Geographic School Bulletins. National Geographic Society.

Warning: These citations may not always be 100% accurate.