APA (7th ed.) Citation

Randall Munroe. (2014). What if?: Serious scientific answers to absurd hypothetical questions. Blackstone Audio.

Chicago Style (17th ed.) Citation

Randall Munroe. What If?: Serious Scientific Answers to Absurd Hypothetical Questions. Inc., [Ashland, Oregon]: Blackstone Audio, 2014.

MLA (9th ed.) Citation

Randall Munroe. What If?: Serious Scientific Answers to Absurd Hypothetical Questions. Blackstone Audio, 2014.