APA (7th ed.) Citation

Heiligman, D., & Humphrey, N. J. A. (2007). Celebrate Christmas. National Geographic.

Chicago Style (17th ed.) Citation

Heiligman, Deborah, and Nathan J. A. Humphrey. Celebrate Christmas. Washington, D.C.: National Geographic, 2007.

MLA (8th ed.) Citation

Heiligman, Deborah, and Nathan J. A. Humphrey. Celebrate Christmas. National Geographic, 2007.

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