APA (7th ed.) Citation

Cowley,Robert, Carr,Caleb, Lukas, J., & Keegen,John. (2001). The collected What if?: Eminent historians imagining what might have been. Putnam.

Chicago Style (17th ed.) Citation

Cowley,Robert, Carr,Caleb, John Lukas, and Keegen,John. The Collected What If?: Eminent Historians Imagining What Might Have Been. Putnam, 2001.

MLA (9th ed.) Citation

Cowley,Robert, et al. The Collected What If?: Eminent Historians Imagining What Might Have Been. Putnam, 2001.