APA (7th ed.) Citation

Card, O. S., Brick, S., & Rudnicki, S. (2007). A war of gifts. Audio Renaissance.

Chicago Style (17th ed.) Citation

Card, Orson Scott, Scott Brick, and Stefan Rudnicki. A War of Gifts. New York: Audio Renaissance, 2007.

MLA (9th ed.) Citation

Card, Orson Scott, et al. A War of Gifts. Audio Renaissance, 2007.